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entitled 'Aviation Fees: Review of Air Carriers' Year 2000 Passenger 
and Property Screening Costs' which was released on April 19, 2005. 

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Report to Congressional Committees: 

April 2005: 

Aviation Fees: 

Review of Air Carriers' Year 2000 Passenger and Property Screening 
Costs: 

GAO-05-558: 

GAO Highlights: 

Highlights of GAO-05-558, a report to congressional committees: 

Why GAO Did This Study: 

The Aviation and Transportation Security Act (ATSA) authorized the 
Transportation Security Administration (TSA) to impose an Aviation 
Security Infrastructure Fee (ASIF) on air carriers to help pay for the 
costs of aviation security services. To impose the ASIF, TSA issued an 
Interim Final Rule (IFR) and required air carriers to report their 
passenger and property screening costs incurred in 2000 on an 
attachment to the IFR referred to as Appendix A. The 2000 screening 
costs reported by air carriers were going to be used to establish the 
ASIF. Based on industry estimates of $1 billion, TSA had estimated that 
the costs incurred by air carriers in 2000 were $750 million, but the 
amounts reported by air carriers totaled $319 million, significantly 
less than expected. To provide the Congress with an independent 
assessment, the Department of Homeland Security Appropriations Act, 
2005 required GAO to review the amount of passenger and property 
screening costs incurred by air carriers in 2000. 

What GAO Found: 

We estimate at a 95 percent confidence level that the amount of 
passenger and property screening costs incurred by air carriers in 2000 
for the 3 major cost components were between $425 million and $471 
million, with a midpoint estimate of $448 million. The difference 
between our midpoint estimate and what the air carriers reported on the 
Appendix A and subsequently paid to TSA is $129 million, as shown in 
the table. 

GAO Estimate of 2000 Passenger and Property Screening Costs: 

[See PDF for image]

Source: GAO analysis. 

[a] See app. I, table 9, for confidence intervals. 

[b] Includes airline employee costs if they performed the screening 
function directly. 

[End of table]

Determining exact cost amounts was not feasible and assumptions were 
required for several reasons including the following: (1) 5 years have 
passed since the costs were incurred, (2) the air carriers’ accounting 
systems were not designed to capture specific passenger and property 
screening costs, and (3) certain cost categories required the 
application of assumptions to identify, categorize, or allocate cost. 
We focused on estimating for 2000 the three primary screening cost 
components listed below. 

* Costs associated with the use of private screening contractors (or 
airline employees if they performed the screening function 
directly)—these were the most significant costs to the air carriers in 
2000. Air carriers typically contracted with private screening 
companies to perform screening on their behalf, and the rates charged 
combined costs such as background checks, training, and uniforms. We 
estimated that air carriers incurred $334 million for this cost 
component, compared to $293 million reported by air carriers on the 
Appendix A. 

* Airport costs related to passenger and property screening—the two 
major screening-related cost categories that airports charged air 
carriers, were costs for law enforcement officers and real estate costs 
for security checkpoints. Based on information obtained from a sample 
of airports, we estimated that air carriers incurred $80 million for 
this cost component, compared to $5 million reported on the Appendix A. 

* Air carriers’ internal costs—these include, among other things, 
installation, operation, maintenance, and testing of screening 
equipment; ground security coordinators; security program management 
and contract administration; and legal and accounting support. Based on 
an analysis of the Appendix A and on information obtained through 
interviews, we estimated that the air carriers incurred $34 million in 
screening costs, compared to $21 million reported in the Appendix A. 

What GAO Recommends: 

We recommend that the Secretary of Homeland Security direct the 
Assistant Secretary, TSA to consider the analysis and estimates in this 
study in determining the limitation on the aggregate air carrier fee 
consistent with ATSA. TSA concurred with our recommendation. TSA 
indicated that it will consider the analysis and estimates in our 
study, as we recommended. 

www.gao.gov/cgi-bin/getrpt?GAO-05-558. 

To view the full product, including the scope and methodology, click on 
the link above. For more information, contact McCoy Williams at (202) 
512-6906 or williamsm1@gao.gov. 

[End of section]

Contents: 

Letter: 

Results in Brief: 

Background: 

Overall Estimate of Passenger and Property Screening Costs: 

Conclusion: 

Recommendation for Executive Action: 

Agency Comments: 

Appendixes: 

Appendix I: Scope and Methodology: 

Develop an Understanding: 

Design of Analytical Framework: 

Data Collection and Cost Estimation: 

Project Work Plan: 

Confidence Intervals: 

Limitations to the Analysis: 

Tables: 

Table 1: GAO Estimate of 2000 Passenger and Property Screening Costs: 

Table 2: Comparison of 2000 Passenger and Property Screening Costs 
Reported in the Appendix A to GAO Estimate: 

Table 3: Costs Associated with the Use of Private Screening 
Contractors: 

Table 4: Airport Costs Related to Passenger and Property Screening: 

Table 5: Air Carrier Internal Costs Related to Passenger and Property 
Screening: 

Table 6: Air Carrier Groupings: 

Table 7: Screening Company Billings and Number of Screeners Prior to 
September 11, 2001: 

Table 8: Number of Airports in Stratified Sample: 

Table 9: Summarization of Cost Estimate Point Estimates and Confidence 
Intervals: 

Abbreviations: 

ASIF: Aviation Security Infrastructure Fee: 

ATA: Air Transport Association of America, Inc. 

ATSA: Aviation and Transportation Security Act: 

CAPPS: Computer Assisted Passenger Prescreening System: 

CEO: Chief Executive Officer: 

DHS: Department of Homeland Security: 

DOT: Department of Transportation: 

FAA: Federal Aviation Administration: 

GSC: Ground Security Coordinator: 

IFR: Interim Final Rule: 

O&D: Origin and Destination: 

OIG: Office of Inspector General: 

SH&E: Simat, Helliesen & Eichner, Inc. 

TSA: Transportation Security Administration: 

Letter April 18, 2005: 

Congressional Committees: 

The terrorist attacks of September 11, 2001, revealed serious long-
standing weaknesses in the nation's aviation security system and 
underscored the need for improvements in order to restore public 
confidence in air travel and to protect our homeland from future 
potential threats. Prior to September 11, 2001, providing aviation 
security was the responsibility of air carriers and airports as part of 
their cost of doing business. However, after September 11, 2001, 
aviation security changed substantially in the United States and the 
responsibility for passenger and property screening shifted to the 
federal government. 

In an effort to make improvements to the aviation security system, 
President Bush signed the Aviation and Transportation Security Act 
(ATSA)[Footnote 1] on November 19, 2001. ATSA created the 
Transportation Security Administration (TSA) whose duties included 
assuming responsibility for the certain aviation security functions 
previously performed by air carriers. To help pay for the costs 
associated with providing these functions, ATSA required TSA to impose 
a uniform fee on passengers. ATSA limited the passenger fee, known as 
the September 11th Security Fee, to $2.50 per passenger enplanement to 
a maximum of $5.00 for a one-way trip. To the extent collections from 
the passenger fee did not cover TSA's costs to provide specified 
aviation security services, ATSA authorized TSA to impose a fee on air 
carriers, called the Aviation Security Infrastructure Fee 
(ASIF).[Footnote 2] However, ATSA[Footnote 3] required TSA to determine 
a statutory cap for the ASIF in the aggregate equal to the total amount 
air carriers had paid for passenger and property screening during 
calendar 2000, the last full calendar year prior to September 11, 
2001.[Footnote 4]

To establish the ASIF, TSA issued an Interim Final Rule (IFR)[Footnote 
5] in February 2002, requiring air carriers to complete and submit an 
attachment to the IFR, titled "Calendar Year 2000 Costs Paid for 
Passenger and Property Screening" (referred to as Appendix A), in which 
they were to itemize costs incurred for passenger and property 
screening during 2000. TSA planned to use the information from Appendix 
A to assist it in determining the statutory cap for the ASIF in the 
aggregate. TSA also planned to use the information to establish each 
air carrier's fee, which air carriers were required to remit to TSA 
each month beginning in 2002. 

At the time the IFR was being developed, TSA forecasted that total 
airline-incurred industry costs for passenger and property screening 
for calendar year 2000 would be $750 million. This estimate was based 
on information that the Air Transport Association of America, Inc. 
(ATA)[Footnote 6] and other airline industry representatives provided 
to the Congress and GAO in 2001. That information indicated that before 
September 11, 2001, the airline industry was spending approximately $1 
billion annually on all airline security. However, when TSA reviewed 
the cost information submitted by air carriers on Appendix A, the sum 
of the airline reported costs totaled approximately $319 million, 
significantly less than what TSA had expected. 

Today, funding for aviation security programs remains a central issue 
because passenger and air carrier security fees are not sufficient to 
fully cover TSA's costs to provide aviation security. TSA's fiscal year 
2004 appropriations for aviation security provided over $3.7 billion 
for civil aviation security services, of which over $3.1 billion was 
for screening activities.[Footnote 7] By contrast, TSA only collected 
about $1.8 billion from passenger security fees and the $319 million 
from the airlines that was credited to the appropriation, meaning the 
federal government funded the remaining $1.6 billion out of general 
revenues. In order to provide the Congress with an independent 
assessment of calendar year 2000 costs paid for passenger and property 
screening, the Department of Homeland Security (DHS) Appropriations 
Act, 2005[Footnote 8] required that we review the amount of passenger 
and property screening costs incurred in calendar year 2000 by domestic 
and foreign carriers departing from U.S. airports and report on the 
results of our work within 6 months of the passage of the act. 

To assist us in evaluating these costs within this time frame, we 
contracted with Simat, Helliesen & Eichner, Inc. (SH&E), a consulting 
firm with significant aviation industry expertise, through a 
competitive award process. SH&E subcontracted with 
PricewaterhouseCoopers LLP for additional accounting and finance 
expertise and with Abt Associates for additional statistical 
capabilities. To provide a basis for the contractors' work, we 
developed an audit strategy to independently determine a reasonable 
estimate of the 2000 passenger and property screening costs incurred by 
the airlines. We oversaw the project and worked closely with 
contractors as they planned and executed their work. To ensure a sound 
approach to the study, we reviewed the contractors' work plans, 
sampling plans, questionnaires, and workpapers. We participated in 
significant meetings, provided continual oversight and feedback, and 
received periodic briefings from the contractors. We performed our work 
in accordance with generally accepted government auditing standards 
from October 2004 through April 2005. Additional details regarding our 
scope and methodology are in appendix I. 

Results in Brief: 

We estimate at a 95 percent confidence level that passenger and 
property screening costs in 2000 for the major cost components were 
between $425 million and $471 million, with a midpoint estimate of $448 
million. The difference between this midpoint estimate and the amount 
the air carriers reported on the Appendix A and subsequently paid to 
TSA is $129 million, as shown in table 1. 

Table 1: GAO Estimate of 2000 Passenger and Property Screening Costs: 

Dollars in millions. 

Private screening contractors costs[B]; 
Air carrier's Appendix A costs: $293; 
GAO estimate[A]: $334; 
Difference: $41. 

Airport costs; 
Air carrier's Appendix A costs: $5; 
GAO estimate[A]: $80; 
Difference: $75. 

Air carriers' internal costs; 
Air carrier's Appendix A costs: $21; 
GAO estimate[A]: $34; 
Difference: $13. 

Total; 
Air carrier's Appendix A costs: $319; 
GAO estimate[A]: $448; 
Difference: $129. 

Source: GAO analysis. 

[A] See app. I, table 9, for related confidence intervals. 

[B] Includes airline employee costs if they performed the screening 
function directly. 

[End of table]

During our review, we considered certain prior estimates of total 
security costs that had been made by ATA and other airline officials. 
These estimates suggested that annual security costs totaled 
approximately $1 billion prior to September 11, 2001. ATA stated that 
the amounts were generalized estimates for all domestic and 
international industry security costs, not just passenger and property 
screening. ATA further explained that they were "best guesses" that 
reflected security costs for functions in addition to passenger and 
property screening. We determined that there was no documented basis 
for these estimates and instead developed our estimate for 2000 based 
on a review of the three primary cost components for passenger and 
property screening shown in table 1. 

We are recommending that the Secretary of Homeland Security direct the 
Assistant Secretary, TSA to consider the analysis and estimates in this 
study in determining the limitation on the aggregate air carrier fee 
consistent with ATSA (49 U.S.C. § 44940(a)(2)(B)(i)). 

TSA indicated from reviewing a draft of this report that it will 
consider the analysis and estimates in our study, as we recommended. 

Background: 

ATSA established TSA as an agency within the Department of 
Transportation and transferred responsibility for civil aviation 
security from the Federal Aviation Administration (FAA) to this newly 
created agency. As mandated by ATSA, TSA is responsible for security in 
all modes of transportation, including conducting the day-to-day 
operations related to security screening for passenger air 
transportation previously conducted by air carriers. 

Prior to the creation of TSA, air carriers were responsible for 
conducting passenger and property screening at U.S. airports. Typically 
air carriers carried out the screening function through contracts with 
security companies. The screening process in place at that time 
included identifying certain passengers for more intense scrutiny with 
the use of Computer Assisted Passenger Prescreening System (CAPPS). In 
addition, passengers were asked a series of questions, such as whether 
they packed their own bags, to help prevent attacks in which passengers 
unknowingly carry dangerous items onto an aircraft. At the security 
checkpoint, passengers were screened by walk-through metal detectors 
and with metal-detecting hand wands if the walk-through metal 
detectors' alarms were activated. Passenger carry-on baggage was 
screened with X-ray equipment. Other procedures that were sometimes 
performed included screening checked baggage for bulk quantities of 
explosives using X-ray computed tomography equipment and the use of 
positive passenger-bag matching to remove bags not owned by those 
aboard the aircraft. 

According to data provided by FAA, prior to September 11, 2001, 
screening procedures were performed at U.S. airports by approximately 
19,500 screeners. Passenger and property screening was one of the most 
substantial aviation security responsibilities assumed by TSA with the 
passage of ATSA. ATSA required that screening of individuals and 
property at U.S. airports be conducted by federal employees and 
companies under contract with TSA. In February 2002, the agency assumed 
the responsibility for passenger and property screening at all U.S. 
commercial airports, except at five airports participating in a pilot 
program, which would operate with private security contractor 
personnel. To continue the daily operations until a federal screener 
workforce was hired, trained, and deployed, TSA contracted with 
incumbent screener companies. On March 1, 2003, pursuant to the 
Homeland Security Act of 2002,[Footnote 9] TSA began to perform its 
transportation security functions as an agency of the Department of 
Homeland Security. 

Prior to September 11, 2001, we were conducting work at the request of 
the Subcommittee on Aviation, House Committee on Transportation and 
Infrastructure, to assess the screening operations of air carriers and 
to determine who should be responsible for screening.[Footnote 10] One 
of the areas under evaluation was the cost of passenger and property 
screening under various alternatives, including how much it would cost 
to have the federal government take over screening functions. In April 
2001, we contacted ATA to obtain information on screening costs 
incurred by air carriers. ATA contacted member carriers and requested 
that they provide information on their costs associated with the 
security screening of passengers and checked baggage. Based on the 
information it said was provided by its members, ATA sent us a memo 
dated August 22, 2001, stating that "ATA believes that the estimated 
costs of implementing federal security requirements and conducting 
required security programs amounts to nearly $1 billion per year for 
the entire industry." In addition, the memo included some detail on the 
direct security costs incurred by ATA members annually, which 
reportedly totaled $511.8 million. 

During a congressional hearing held on September 19, 2001, Delta's then 
Chief Executive Officer (CEO) corroborated the $1 billion security cost 
estimate when he stated in response to a question raised by a member of 
Congress that "relative to the security measures, we as an industry 
probably spend on the order of a billion dollars or so per year now on 
security."[Footnote 11] Subsequently, responding to TSA's proposal to 
increase the ASIF, ATA stated that the amounts cited by airline 
executives were generalized estimates for all domestic and 
international industry security costs; not just passenger and property 
screening. ATA further explained that the estimates were "best guesses" 
that reflected security costs for functions in addition to passenger 
and property screening. 

When we requested documentation supporting this estimate as part of our 
current review, ATA responded that the estimate provided in its August 
2001 memo to us was a rough estimate of security costs based on limited 
information provided by a handful of air carriers in response to a less-
than-rigorous survey. ATA added that it did not have and could not 
obtain detailed and consistent cost data due to the various ways in 
which air carriers provided security services. Further, ATA stated that 
air carriers were not consistent in recording and accounting for the 
security-related costs in their internal systems. The substantial 
difference between costs reported earlier by the aviation industry and 
those reported by air carriers in their Appendix A submissions 
precipitated the legislative mandate that GAO review passenger and 
property screening costs. Details of our review and our estimate of 
calendar year 2000 passenger and property screening costs follow. 

Overall Estimate of Passenger and Property Screening Costs: 

With the assistance of our contractors, we estimate at a 95 percent 
confidence level that the airline industry's costs to provide passenger 
and property screening in calendar year 2000 for the 3 major cost 
components was between $425 million and $471 million, with a midpoint 
estimate of $448 million. This amount is $129 million more than the 
$319 million reported and paid by the air carriers to TSA. 

We found that determining exact cost amounts was not feasible for 
several reasons, including the following: 

* Five years had passed since the costs were incurred. 

* The air carriers' accounting systems were not designed to capture 
specific passenger and property screening costs at the level of detail 
TSA had requested. 

* Certain cost categories required the application of assumptions to 
identify, categorize, or allocate cost. 

Given this, we focused on estimating for 2000 the 3 primary screening 
cost components covered in Appendix A: (1) costs associated with the 
use of private screening contractors (or airline employees if they 
performed the screening function directly), (2) airport costs related 
to passenger and property screening that were passed on to air 
carriers, and (3) air carrier internal costs associated with screening 
functions. Our estimate of each of these costs components is shown in 
table 2. 

Table 2: Comparison of 2000 Passenger and Property Screening Costs 
Reported in the Appendix A to GAO Estimate: 

Dollars in millions. 

Private screening contractors costs[B]; 
Air carrier's Appendix A costs: $293; 
GAO estimate[A]: $334; 
Difference: $41. 

Airport costs; 
Air carrier's Appendix A costs: $5; 
GAO estimate[A]: $80; 
Difference: $75. 

Air carriers' internal costs; 
Air carrier's Appendix A costs: $21; 
GAO estimate[A]: $34; 
Difference: $13. 

Total; 
Air carrier's Appendix A costs: $319; 
GAO estimate[A]: $448; 
Difference: $129. 

Source: GAO analysis. 

[A] See app. I, table 9, for related confidence intervals. 

[B] Includes airline employee costs if they performed the screening 
function directly. 

[End of table]

In 2000, air carriers were responsible for providing and paying for the 
costs associated with screening passengers and property prior to 
boarding aircraft. Air carriers typically contracted with private 
companies to perform these services on their behalf. Airports were 
required to restrict access to the preboarding sterile area and to 
provide law enforcement officers to respond to potential incidents at 
the screening checkpoints within a certain time frame. To varying 
degrees, such airport-incurred costs were passed on to air carriers 
through airport rates and charges. In addition, air carriers incurred 
certain internal costs in carrying out these functions, such as the 
costs of managing and providing legal support for the security company 
contracts. 

Costs Associated with the Use of Private Screening Contractors: 

Table 3: Costs Associated with the Use of Private Screening 
Contractors: 

Dollars in millions. 

Private screening contractors costs[B]; 
Air carrier's Appendix A costs: $293; 
GAO estimate[A]: $334; 
Difference: $41. 

Source: GAO analysis. 

[A] See app. I, table 9, for related confidence intervals. 

[B] Includes airline employee costs if they performed the screening 
function directly. 

[End of table]

Labor costs associated with screening passengers and property were the 
most significant screening-related cost to the air carriers in 2000. 
Air carriers typically contracted with private screening companies to 
perform these services on their behalf, and the rates charged combined 
many costs, such as background checks, training, and uniforms. In some 
instances, air carrier employees performed the screening. We estimate 
at a 95 percent confidence level that the costs associated with the use 
of private screening contractors (or air carrier employees if they 
performed the screening function directly) during 2000 were between 
$313 million and $355 million, with a midpoint estimate of $334 
million. This is about $41 million more than the $293 million reported 
on Appendix A by the air carriers for this cost component. 

To estimate these direct screening costs, we identified the major 
companies providing screening services in 2000 and requested their 
billing records. Over 70 companies provided screening services in 2000, 
with 10 companies representing over 80 percent of the industry and 2 
companies comprising almost half of the industry. We asked the top 10 
companies how much they had billed for screening services by air 
carriers and received usable information from 9 of them. Although we 
received over 7,000 invoices from the remaining and largest company 
during 2000, the data were incomplete and could not be used to project 
estimates for the remaining companies. For the 9 companies that did 
provide useable data, we determined that they had billed the air 
carriers approximately $208 million for screening-related services in 
2000. These companies also provided numerous non-screening-related 
services (for example, wheelchair assistance and skycap service), which 
we excluded from our estimate. Using a regression analysis[Footnote 12] 
from the useable data, we estimate total screening company costs are 
$334 million. We performed two other tests on the data to assess 
whether our overall assumptions used to estimate these costs were 
reasonable. Both of these methods yielded results that were within the 
range provided by the regression analysis. 

Airport Costs Related to Passenger and Property Screening: 

Table 4: Airport Costs Related to Passenger and Property Screening: 

Dollars in millions. 

Airport costs; 
Air carrier's Appendix A costs: $5; 
GAO estimate[A]: $80; 
Difference: $75. 

Source: GAO analysis. 

[A] See app. I, table 9, for related confidence intervals. 

[End of table]

Regarding the second cost category--airport costs related to passenger 
and property screening that were passed on to the air carriers--we 
estimate at a 95 percent confidence level that air carriers incurred 
costs between $71 million and $89 million, with a midpoint estimate of 
$80 million. This was well above the $5 million reported by the air 
carriers. 

The two major cost categories that airports charged to the air carriers 
as screening-related costs were costs for law enforcement officers and 
real estate costs associated with security checkpoints. To estimate 
these airport costs, we selected a representative sample of the 
approximately 430 U.S. airports that screened passengers in 2000 and 
extrapolated[Footnote 13] the information obtained to the whole 
industry. The stratified sample included the 20 airports with the 
largest number of estimated screened passengers plus an additional 50 
airports. The 70 sampled airports accounted for approximately 75 
percent of the total estimated 530.4 million screened passengers during 
2000 at U.S. airports. 

For each airport in the sample, we attempted to interview the 
appropriate airport officials and collect (1) specific screening-
related costs charged to or incurred by the air carriers, (2) airport 
rate-making methodologies, and (3) air carrier use agreements. We used 
the information obtained to estimate total airport charges and believe 
that our methodology and underlying data provide a reasonable basis for 
our estimate. Fifty-nine of the 70 airports, including 19 of the 20 
largest airports, and 40 of the 50 additional airports, provided data 
that we used to extrapolate to the remaining airports. 

Costs for Law Enforcement Officers: 

Based on the review of information from the 59 airports, we estimate at 
a 95 percent confidence level that air carriers incurred costs for law 
enforcement officers with screening-related responsibilities between 
$56 million and $76 million, with a midpoint estimate of $66 million. 
This is significantly higher than the $1.5 million reported by the air 
carriers. According to the air carriers, they did not report these 
costs for two main reasons: (1) information on law enforcement 
officers' costs and time spent completing specific duties was not 
readily available; thus many air carriers did not attempt to estimate 
these costs and (2) they contend that they are still paying law 
enforcement officers' costs. 

The estimate for this cost component would have been even higher if all 
airports had passed on law enforcement officers' charges to the air 
carriers. For example, at Los Angeles International Airport, the 
largest U.S. airport in terms of screened passengers, none of the costs 
associated with providing law enforcement officers were passed on to 
the air carriers. These costs were covered by nonairline revenues, such 
as concession revenues. In contrast, at Dallas Fort Worth and many 
other airports, 100 percent of law enforcement officer costs associated 
with checkpoint security were directly billed to the air carriers. In 
these cases, 100 percent of the charge was used in calculating our 
estimate. Other sampled airports combined law enforcement officers' 
costs with other terminal costs and varied in how they passed costs on 
to air carrier tenants. If the airport allocated a portion of its 
airportwide law enforcement officers' budget to the terminal cost 
center, we estimated the share of terminal law enforcement officer 
costs related to passenger and property screening, and then included in 
our estimate only the share of such costs that was passed on to the 
airlines based on the airports' rates and charges methodology. 

Costs for Security Checkpoint Space: 

Airport charges for the leased space where screening checkpoints were 
located varied greatly among the sampled airports. However, we observed 
some general tendencies. If the checkpoint was located in space that 
was rented by air carrier tenants, we calculated the real estate cost 
based on square footage and the applicable rental rate. On the other 
hand, if the checkpoint was located in airport space for which air 
carrier tenants were not directly charged, we estimated the cost based 
on the airport's rate structure. Specifically, if the costs for public 
space were absorbed by the airport or were not factored into the cost 
pool used to determine air carrier space rental rates, we did not 
assign any cost to the airlines to calculate our estimate. Whereas, if 
the costs for public space were rolled into the cost pool to determine 
airline rental rates, then the air carrier indirectly paid for the 
space and we included the cost in our estimate. Based on the sample of 
59 airports, we estimate at a 95 percent confidence level that air 
carriers incurred security real estate costs between $11 million and 
$15 million, with a midpoint estimate of $13 million compared to the 
$3.4 million reported on Appendix A by the air carriers. 

Air Carrier Internal Costs Related to Passenger and Property Screening: 

Table 5: Air Carrier Internal Costs Related to Passenger and Property 
Screening: 

Dollars in millions. 

Air carriers' internal costs; 
Air carrier's Appendix A costs: $21; 
GAO estimate[A]: $34; 
Difference: $13. 

Source: GAO analysis. 

[A] See app. I, table 9, for related confidence intervals. 

[End of table]

Air carrier internal costs include, among other things, installation, 
operation, maintenance, and testing of screening equipment; ground 
security coordinators; security program management and contract 
administration; and legal and accounting support. To estimate the air 
carrier internal costs, we first grouped the air carriers into 
categories based on types of operations as shown in table 6. 

Table 6: Air Carrier Groupings: 

Type: Legacy; 
Description: Major hub and spoke carriers; 
Examples: American, Delta, United. 

Type: Low cost; 
Description: Primarily nonhub carriers; 
Examples: Southwest, JetBlue. 

Type: Regional; 
Description: Carriers operating regional jet and commuter aircraft; 
Examples: Comair, Mesa, Skywest. 

Type: Foreign; 
Description: Non-U.S. airlines; 
Examples: Air Canada, British Airways. 

Type: Other; 
Description: Niche carriers; 
Examples: Hawaiian, U.S. Airways Shuttle. 

Source: GAO analysis. 

[End of table]

We then reviewed and analyzed the air carrier Appendix A cost 
submissions, interviewed 12 air carriers that together account for 63 
percent of total estimated screened passengers in 2000. In addition, we 
reviewed workpapers prepared by independent auditors as part of the 
audit of certain air carriers' Appendix A submissions. Based on the 
information obtained from these sources, we designed cost-estimating 
methodologies and applied them to air carriers based on their grouping, 
relying on the assumption that air carriers of the same type would have 
similar cost structures. For example, legacy carriers with major hubs 
would likely incur certain costs, such as operational maintenance of 
screening equipment, which other regional or low-cost carriers might 
not typically incur. This estimation resulted in approximately $13 
million more in air carrier internal costs in our estimate than the air 
carriers reported in the Appendix A. 

Conclusion: 

We estimate that passenger and property screening costs incurred by air 
carriers in calendar year 2000 for the major cost components were $448 
million, resulting in a difference of $129 million from air carrier-
reported costs of $319 million. As such, TSA is not obtaining all of 
the proceeds of the ASIF authorized by ATSA. 

Recommendation for Executive Action: 

We are making one recommendation for executive action that will allow 
TSA to more fully collect the ASIF, as authorized by ATSA. 
Specifically, we recommend that the Secretary of Homeland Security 
direct the Assistant Secretary, Transportation Security Administration, 
to consider the analysis and estimates in this study in determining the 
limitation on the aggregate air carrier fee consistent with ATSA (49 
U.S.C. § 44940(a)(2)(B)(i)). 

Agency Comments: 

We requested comments on a draft of this report from the Secretary of 
Homeland Security or his designee. TSA indicated that it will consider 
the analysis and estimates in our study as we recommended. TSA also 
provided us with techincal comments, which we incorporated where 
appropriate. 

We are sending copies of this report to the Secretary of Homeland 
Security and the Assistant Secretary, Transportation Security 
Administration. We will also make copies available to others upon 
request. In addition, the report is available at no charge on the GAO 
Web site at [Hyperlink, http://www.gao.gov]. 

Should you or your staff have any questions on matters discussed in 
this report, please contact me at (202) 512-6906 or [Hyperlink, 
williamsm1@gao.gov] or Casey Keplinger, Assistant Director, at (202) 
512-9323 or [Hyperlink, keplingerc@gao.gov]. Other major contributors 
to this report were Sharon Byrd, Heather Dunahoo, Jeff Jacobson, Carla 
Lewis, Gloria Medina, Zakia Simpson, and Bethany Smith. 

Signed by: 

McCoy Williams: 
Director, Financial Management and Assurance: 

List of Congressional Committees: 

The Honorable Judd Gregg: 
Chairman: 
The Honorable Robert C. Byrd: 
Ranking Minority Member: 
Subcommittee on Homeland Security: 
Committee on Appropriations: 
United States Senate: 

The Honorable Conrad Burns: 
Chairman: 
The Honorable John D. Rockefeller IV: 
Ranking Minority Member: 
Subcommittee on Aviation: 
Committee on Commerce, Science, and Transportation: 
United States Senate: 

The Honorable Harold Rogers: 
Chairman: 
The Honorable Martin Olav Sabo: 
Ranking Minority Member: 
Subcommittee on Homeland Security: 
Committee on Appropriations: 
House of Representatives: 

The Honorable John L. Mica: 
Chairman: 
The Honorable Jerry F. Costello: 
Ranking Democratic Member: 
Subcommittee on Aviation: 
Committee on Transportation and Infrastructure: 
House of Representatives: 

[End of section]

Appendixes: 

Appendix I: Scope and Methodology: 

To assist us in evaluating passenger and property screening costs 
incurred by air carriers in 2000, we contracted with Simat, Helliesen & 
Eichner, Inc. (SH&E), a consulting firm with significant aviation 
industry expertise, through a competitive award process. SH&E 
subcontracted with PricewaterhouseCoopers LLP for additional accounting 
and finance expertise and with Abt Associates for additional 
statistical capabilities. To provide a basis for the contractors' work, 
we developed an audit strategy to independently determine a reasonable 
estimate of the 2000 passenger and property screening costs incurred by 
the airlines. We oversaw the project and worked closely with 
contractors as they planned and executed their work. To ensure a sound 
approach to the study, we reviewed the contractors' work plans, 
sampling plans, questionnaires, and workpapers. We participated in 
significant meetings, provided continual oversight and feedback, and 
received periodic briefings from the contractors. 

Develop an Understanding: 

To develop an understanding of the passenger and property screening 
process and the issues involved in measuring associated costs, we 
conducted numerous interviews and informational meetings with key 
stakeholders, including representatives of the Transportation Security 
Administration (TSA); the Department of Transportation's (DOT) Office 
of Inspector General (OIG); the Department of Homeland Security's (DHS) 
OIG; and the Air Transportation Association of America, Inc., as well 
as current and former Federal Aviation Administration (FAA) security 
officials. We also interviewed subject matter experts, current and 
former airline officials with security-related responsibilities at both 
the corporate headquarters and airport station levels, finance and 
operations officials at major airports, and other individuals. 

We reviewed numerous documents that were publicly available or made 
available to us for the purposes of this study. These included public 
and airline industry comments on the imposition of the Aviation 
Security Infrastructure Fee; regulatory documents concerning FAA 
requirements for passenger and property screening in calendar year 2000 
and other regulatory documents; prior studies and testimonies on 
passenger and property screening; TSA analyses of passenger and 
property screening costs; and the workpapers of the DHS OIG, which was 
conducting a separate review of airline passenger and property 
screening costs in 2000. 

We thoroughly reviewed and analyzed cost data that had been submitted 
by airlines on Appendix A submissions to understand the types of costs 
that were identified, the relative magnitude of those costs, and how 
the costs were determined. We also used the Appendix A submissions to 
perform an initial benchmarking analysis to identify obvious outliers 
and potential gaps in certain cost categories. 

Design of Analytical Framework: 

We determined the primary cost drivers for providing passenger and 
property screening services in 2000 and designed an approach to measure 
these costs. Based on the understanding of the screening process 
acquired during the planning stage of our review, we identified three 
primary cost components: 

1. Costs associated with the use of private screening contractors (or 
airline employees if they performed the screening function directly). 

2. Airport costs related to passenger and property screening. 

3. Internal airline costs. 

Data Collection and Cost Estimation: 

A database of screened passengers by airport and airline in calendar 
year 2000 was prepared to provide the basis for developing unit cost 
rates for use in the expansion of sampled results to an overall U.S. 
system total. These data were estimated using publicly available 
airline passenger traffic data sources, including the DOT Passenger 
Origin-Destination Survey; the DOT T-100 Flight Segment database; the 
DOT Part 298C Passenger Data; and origin-destination passenger data as 
adjusted by Database Products, Inc. 

We determined that an origin and destination (O&D) measure was the most 
appropriate metric for use in the analysis, since other traffic 
measures, such as enplanements, include a substantial number of 
connecting passengers at hub airports who do not pass through 
screening. However, we did include inbound international passengers who 
connect to domestic flights and are re-screened at U.S. gateway 
airports. The screened passenger estimates also include certain 
domestic to international connecting passengers who require a second 
screening because they change terminals when connecting to their 
international flights. The database identifies calendar year 2000 
screened passengers by airport, airline, and traffic category. As 
possible, the database was validated by analysis and reconciliation 
with other data sources. The screened passenger database was used as a 
basis for expansion of sample data in each of the three primary cost 
analyses. 

Project Work Plan: 

Our project work plan included three major work elements designed to 
independently quantify the costs incurred by airlines within each of 
three identified primary cost areas, which are explained below. 

Screening Industry Cost Analysis: 

We compiled and classified billing records from nine private screening 
companies that generated over $200 million in calendar year 2000 
screening revenues and represented approximately 62 percent of the 
overall U.S. passenger and property screening market. We assumed that 
companies provided full billing records and could not independently 
verify the data. A summary of these data is provided in table 7. 

Table 7: Screening Company Billings and Number of Screeners Prior to 
September 11, 2001: 

Screening company: 1; 
Billings: $67,151,628; 
Screening employees: 4,201. 

Screening company: 2; 
Billings: $41,975,478; 
Screening employees: 2,833. 

Screening company: 3; 
Billings: $57,312,687; 
Screening employees: 2,426. 

Screening company: 4; 
Billings: $9,606,700; 
Screening employees: 615. 

Screening company: 5; 
Billings: $8,196,675; 
Screening employees: 565. 

Screening company: 6; 
Billings: $3,334,114; 
Screening employees: 509. 

Screening company: 7; 
Billings: $7,528,050; 
Screening employees: 477. 

Screening company: 8; 
Billings: $6,961,848; 
Screening employees: 275. 

Screening company: 9; 
Billings: $6,318,085; 
Screening employees: 174. 

Screening company: Total; 
Billings: $208,385,265; 
Screening employees: 12,075. 

Source: GAO analysis. 

[End of table]

Using the data collected for the nine screening companies, we used a 
regression model to estimate total screening costs. The basic form of a 
simple linear regression model is as follows: 

[See PDF for formula]

[End of figure]

Since it is reasonable to assume that a company with zero employees 
would have zero screening costs, we have used a model that assumes the 
intercept term (beta zero) is zero.[Footnote 14] Based on the data for 
the nine screening companies, the estimated beta 1 parameter is 17,014. 
In other words, for every employee, the model predicts $17,014 in 
screening costs. 

Thus, screening costs can be estimated through the following: 

Screening costs per company = $17,014 x number of screening employees: 

This model shows a strong correlation between the number of screening 
employees and the screening costs per company and provides a 
statistically significant relationship between the number of screening 
employees and screening costs per company. A comparison of the 
predicted values and the actual values shows a difference of about 1.4 
percent for the 9 screening companies. In addition, model diagnostics 
indicate that the model provides a reasonable fit to the data. 

Using this model, we calculated a predicted value for each of the 10 
screening companies with no billing data and the remaining screening 
employees not identified within the top 19 screening companies. A 95 
percent confidence interval around the estimate ranges from $313 
million to $355 million. 

We considered several options for estimating total screening costs, 
such as a simple ratio of billings to employees and a regression model 
based on number of passengers rather than number of employees. However, 
we used the regression method based on number of employees because it 
provided the most precise estimate (i.e., the narrowest confidence 
interval). 

Airport Cost Analysis: 

We interviewed, collected financial data, and analyzed screening-
related costs at 59 U.S. airports, including 19 of the 20 largest 
airports and a cross section of other airports of different sizes. 
These 59 airports accounted for approximately 70 percent of total U.S. 
screened passengers in 2000. Through the interviews, we collected 
information on airport rate-making methodologies, airline use 
agreements, and specific screening-related costs that were recovered 
from the airlines in calendar year 2000. The data obtained were used to 
quantify screening costs at the sample airports and then extrapolated 
to the total U.S. airport system. An overview of the approach to 
estimating airport costs is summarized below. 

* Developed an understanding of airport responsibilities for passenger 
and property screening and identified the types of screening-related 
costs were incurred at airports that may have been passed on to the 
airlines. 

* Conducted informational interviews with senior officials at selected 
airports. 

* Designed a stratified sample of U.S. airports. 

* Developed interview protocol and guidelines. 

* Scheduled interviews with airport officials. 

* Conducted interviews. 

* Obtained backup documentation and clarification. 

* Quantified costs by airport and calculated unit cost rates. 

* Extrapolated sample results to U.S. airport system total. 

The stratified sample of airports used to develop our estimate was 
drawn from the 400 largest U.S. airports, based on outbound O&D 
passengers,[Footnote 15] which represented 99.9 percent of total 
estimated screened passengers at U.S. airports in calendar year 2000. 
The 400 airports were divided into 5 strata based on the volume of 
outbound O&D passengers. Because the 20 largest airports accounted for 
approximately one-half of total U.S. O&D passengers, all 20 of these 
major airports were included in the airport sample. 

Fifty airports were randomly sampled from strata 2 to 5. The sample 
contained 20 airports from Stratum 2, and 10 airports each from strata 
3 to 5. Airports in strata 2 to 5 were then divided into 10 groups, 
each with 5 airports from the various strata, to ensure that a 
representative, unbiased sample would be interviewed, even if there 
were not enough time to interview all of the sample airports. However, 
interviews were ultimately attempted with all sample airports in strata 
2 to 5 as shown in table 8. 

Table 8: Number of Airports in Stratified Sample: 

Stratum: 1; 
Estimated screened passengers: 270,557,510; 
Percentage of total: 51.0%; 
No. of airports: 20; 
Sample airports: 20. 

Stratum: 2; 
Estimated screened passengers: 136,932,121; 
Percentage of total: 25.8%; 
No. of airports: 27; 
Sample airports: 20. 

Stratum: 3; 
Estimated screened passengers: 69,321,908; 
Percentage of total: 13.1%; 
No. of airports: 34; 
Sample airports: 10. 

Stratum: 4; 
Estimated screened passengers: 33,284,409; 
Percentage of total: 6.3%; 
No. of airports: 60; 
Sample airports: 10. 

Stratum: 5; 
Estimated screened passengers: 20,305,673; 
Percentage of total: 3.8%; 
No. of airports: 289; 
Sample airports: 10. 

Total; 
Estimated screened passengers: 530,401,621; 
Percentage of total: 100.0%; 
No. of airports: 430[A]; 
Sample airports: 70. 

Source: SH&E. 

[A] After the sample design was completed, a complete list of airports 
that had passenger and property screening in 2000 was provided by 
former FAA officials now with TSA. That list identified 430 airports, 
compared to the 400 airports from which the stratified sample was 
drawn. The additional 30 airports accounted for only 0.1 percent of 
estimated screened passengers. 

[End of table]

The goal of the airport survey was to collect cost information for at 
least 50 of 70 sample airports (including Stratum 1 airports) in order 
to extrapolate the results to the total population of U.S. airports. We 
interviewed representatives from 59 of the 70 sample airports. Airports 
whose representatives were not interviewed were generally unable to 
participate because of schedule issues. For two airports, we relied on 
DHS OIG workpapers, in lieu of a study team interview. 

The estimated airport screening costs borne by airlines were correlated 
with airport size. Our sampling and analysis strategy was designed to 
use this relationship to obtain the highest possible precision from the 
sample airport observations. Sixty of the 68 airports we attempted to 
contact provided usable responses within the time limits of this study. 
Across the strata, response rates ranged from 70 percent to 95 percent. 
Accordingly, we assigned each responding airport a sampling weight 
equal to the number of airports in its stratum (N) divided by the 
number of responding airports (n) to extrapolate to the total airport 
population. 

Airline Internal Cost Analysis: 

The objective of the airline internal cost analysis was to prepare an 
independent estimate of airline internal costs related to passenger and 
property screening that were not captured through the separate analyses 
of contract screener industry costs and airport costs. To develop an 
understanding of airline responsibilities for passenger and property 
screening and to identify internal cost functions, we reviewed FAA 
regulations and the Air Carrier Standard Security Plan for calendar 
year 2000. We also interviewed airline officials who had been in 
security-related positions in calendar year 2000. 

The analysis is based on several sources of information, including the 
airline Appendix A submissions and accompanying notes. We relied on 
information obtained from interviews that were conducted with officials 
from 12 airlines that accounted for 63 percent of total estimated 
calendar year 2000 screened passengers at U.S. airports. Finally, we 
reviewed and relied upon workpapers prepared by the airlines' 
independent auditors and information compiled by the DHS OIG during its 
recent review. 

The airline internal cost analysis focused on 11 cost categories from 
Appendix A: 

* Line 16--Screening Equipment Installation: 

* Line 17--Operating, Maintenance and Testing of Screening Equipment: 

* Line 24--Ground Security Coordinators: 

* Line 25--Security Program Management: 

* Line 26--Security Contract Administration and Oversight: 

* Line 28--Legal Support: 

* Line 29--Accounting Support: 

* Line 30--Other Administrative Support: 

* Line 31--Insurance: 

* Line 34--Fees for Oversight of Consortium Contracts: 

* Line 35--Other (includes fines): 

In performing the analysis, airlines were classified into five groups 
to identify potential differences in operating and cost 
characteristics: 

* Legacy: Major hub and spoke carriers (e.g., American, Delta, and 
United). 

* Low Cost: Primarily nonhubbing carriers (e.g., Southwest and 
JetBlue). 

* Regional: Carriers operating regional jet and commuter aircraft 
(e.g., Comair, Mesa, and Skywest). 

* Foreign: Non-U.S. airlines (e.g., Air Canada, British Airways, and 
Mexicana). 

* Other: Niche carriers (e.g., Hawaiian, Midwest Express, and US 
Airways Shuttle). 

We developed two analytical approaches for estimating airline internal 
costs. The first approach applies to 6 of the Appendix A costs 
categories (Lines 16, 17, 25, 26, 28, and 29) and utilizes information 
reported in Appendix A and the accompanying footnotes to estimate total 
industrywide airline internal costs. Airline interviews and auditor 
workpaper reviews indicated that the air carriers that submitted costs 
for these six line items generally followed reasonable and logical 
methodologies to develop their estimates. Therefore, we relied on 
average unit cost rates for airlines that did identify these line item 
costs and applied those to nonreporting and nonfiling carriers within 
individual carrier groupings to estimate the unreported costs. 

A separate bottom-up approach was used to estimate costs for Line 24-
Ground Security Coordinators (GSC) and Line 35-Other Costs (including 
FAA fines). Costs for GSC functions were developed from study team 
estimates of the total number of qualified GSCs in 2000, applicable 
training requirements, the total number of checkpoints at U.S. airports 
in 2000, the average amount of time spent on monthly checkpoint audits 
and daily tasks, and an average fully burdened wage rate for GSC 
airline employees. For Line 35-Other Costs (including FAA fines), we 
used the midpoint of Appendix A costs, which were known to be 
understated, and FAA Quarterly Enforcement Reports to estimate industry 
costs for this category. 

Independent estimates were not prepared for 3 costs categories (Lines 
30, 31, and 34), since it was concluded that the amounts reported in 
Appendix A were representative of overall airline industry costs. 

Confidence Intervals: 

The confidence intervals for each of the statistically derived 
estimates referred to throughout the report are presented in table 9. 

Table 9: Summarization of Cost Estimate Point Estimates and Confidence 
Intervals: 

Dollars in millions. 

Private screening contractors costs[A]; 
Point estimate: $334; 
Confidence interval at a 95% confidence level +(-): $21. 

Airport costs; 
Point estimate: $80; 
Confidence interval at a 95% confidence level +(-): $9. 

Law enforcement officers; 
Point estimate: $66; 
Confidence interval at a 95% confidence level +(-): $10. 

Security checkpoint space; 
Point estimate: $13; 
Confidence interval at a 95% confidence level +(-): $2. 

Air carriers' internal costs; 
Point estimate: $34; 
Confidence interval at a 95% confidence level +(-): $0. 

Overall estimate and confidence interval of passenger and property 
screening costs; 
Point estimate: $448; 
Confidence interval at a 95% confidence level +(-): $23. 

Source: GAO analysis. 

Note: Numbers may not add due to rounding. 

[A] Includes airline employee costs if they performed the screening 
function directly. 

[End of table]

Limitations to the Analysis: 

In preparing the cost estimates, we generally relied upon 
representations and information provided by air carriers, government 
agencies, airports, and screening companies. Procedural limitations 
were encountered related to (1) the amount of time that has passed 
since calendar year 2000, (2) access and availability of cost or 
accounting records, (3) access and availability of individuals due to 
employee turnover, (4) corporate structural changes (i.e., bankruptcy, 
acquisitions, etc.), and (5) record retention policies. Certain cost 
categories required the application of assumptions to identify, 
categorize, or allocate cost due to the structure, limitations, or both 
of the air carrier, airport, or screening company accounting systems. 
While nearly all entities contacted were cooperative, the following 
information or documents requested were not provided consistently from 
all air carriers and other stakeholders: (1) air carrier calendar year 
2000 Section 108 Security Plans, (2) identification or allocation of 
time and expense related to ground security coordinators, (3) full and 
complete billing records and supporting documentation for all screening 
companies, and (4) full and complete information on airport rates and 
charges structures at individual airports and records on airport rental 
payments received from airlines. 

We also identified certain security-related functions for which we were 
not able to measure the cost given the lack of available information 
and the limited time frame to complete the work. Examples of such costs 
include (1) security-related real estate costs for airline-owned 
terminals; (2) costs associated with Computer Assisted Passenger 
Prescreening System (CAPPS); and (3) costs related to Positive 
Passenger Bag Match. Although analyzing the costs of these additional 
functions would likely increase our estimate, we were unable to 
determine costs associated with these functions within our time frame 
and believe that we have captured the primary cost components. 

We requested comments on a draft of this report from the Secretary of 
Homeland Security or his designee, as discussed in the Agency Comments 
section. 

We performed our work in accordance with generally accepted government 
auditing standards from October 2004 through April 2005. 

(195058): 

FOOTNOTES

[1] Pub. L. No. 107-71, 115 Stat. 597 (Nov. 19, 2001). 

[2] 49 U.S.C. § 44940(a)(1), (2)(A). 

[3] 49 U.S.C. § 44940(a)(2)(B)(i). 

[4] For purposes of this review and the calculation of the ASIF, 
property is defined as mail, cargo, carry-on and checked baggage and 
any other articles transported by an air carrier excluding property 
transported under the "Known Shipper Program."

[5] Aviation Security Infrastructure Fees, 67 Fed. Reg. 7926 (Feb. 20, 
2002). 

[6] ATA is the largest trade organization of U.S. air carriers, 
representing 23 U.S airline members and 5 foreign-based airlines in 
2000. 

[7] Department of Homeland Security Appropriations Act, 2004, Pub. L. 
No. 108-90, 117 Stat. 1137, 1141 (Oct. 1, 2003). 

[8] Pub. L. No. 108-334, 118 Stat. 1298, 1303 (Oct. 18, 2004). 

[9] Pub. L. 107-296, 116 Stat. 2135 (Nov. 25, 2002). 

[10] GAO, Aviation Security: Weaknesses in Airport Security and Options 
for Assigning Screening Responsibility, GAO-01-1165T (Washington, D.C.: 
Sept. 21, 2001). 

[11] Statement of Leo F. Mullin, Chairman and CEO of Delta Airlines at 
congressional hearing held on September 19, 2001, before the House 
Committee on Transportation and Infrastructure, H.R. 2891, To Preserve 
the Continued Viability of the United States Air Transportation System. 

[12] Regression analysis is a statistical method of measuring the 
extent to which variations in one variable are associated with 
variations in other variables. 

[13] See our scope and methodology in app. I for an explanation on how 
we extrapolated the results of our sample evaluation. 

[14] We considered a regression model including an intercept parameter; 
however, the estimated parameter is not statistically significant from 
zero. 

[15] Outbound O&D passengers were used as a proxy of screened 
passengers to develop the airport sample, which proceeded in parallel 
with the estimation of the number of screened passengers in calendar 
year 2000. 

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