Auxiliary Establishment - Auxiliary establishments are establishments that are primarily involved in rendering support services for other establishments within the same corporation or enterprise, such as warehouses, distribution centers and central administrative offices. Auxiliary establishments with shipping activity were included in the CFS.

Average Miles Per Shipment - Average miles per shipment are computed by dividing the total miles traveled by the total number of shipments.  This statistic is provided in the CFS by mode, commodity, shipment weight, and industry.

Business Register - The Census Bureau's Business Register is a database of all known establishments located in the United States or its territories, where an establishment is defined as a single physical location where business transactions take place or services are performed. The CFS sample was selected from the approximately 710,000 eligible establishments on the Business Register. Eligible establishments consisted of those classified as mining, manufacturing, wholesale, electronic shopping and mail-order houses, fuel dealers, and publishers.

Cell Suppression - Cell suppression is used in CFS tables for two purposes: (1) protecting sensitive cells posing disclosure risks as indicated with a ‘D', and; (2) masking estimates of poor data quality or otherwise not meeting publication standards. The second form of suppression is often the result of high sampling variability and is represented by an ‘S' in the respective cell.

Coefficient of Variation (CV) - See Sampling error

Commodity - Products that an establishment produces, sells, or distributes. This does not include items that are considered as excess or waste of the establishment's operation. Respondents reported the description and the five-digit Standard Classification of Transported Goods (SCTG) code for the commodity contained in the shipment. Shipments involving multiple commodities are classified as the commodity with the greatest weight in the total shipment.

Confidentiality - In accordance with Title 13 of the United States Code, no estimates may be published that would disclose the operations of an individual firm. Title 13 authorizes the Census Bureau to conduct censuses and surveys. Section 9 of the same Title requires that any information collected from the public under the authority of Title 13 be maintained as confidential. Section 214 of Title 13 and Sections 3559 and 3571 of Title 18 of the United States Code provide for the imposition of penalties of up to 5 years in prison and up to $250,000 in fines for wrongful disclosure of confidential census information.

Disclosure Avoidance - Disclosure is the release of data that have been deemed confidential. It generally reveals information about a specific individual or establishment and/or permits deduction of sensitive information about a particular individual or establishment. Disclosure avoidance is the process used to protect the confidentiality of the survey data provided by an individual or firm. For the CFS, the primary method of disclosure avoidance is Noise Infusion: Noise infusion is a method of disclosure avoidance in which values for each shipment are perturbed prior to tabulation by applying a random noise multiplier. Disclosure protection is accomplished in a manner that causes the vast majority of cell values to be perturbed by at most a few percentage points. In certain circumstances, some individual cells may be suppressed on a case by case basis for additional disclosure avoidance. In these cases the data are replaced with a "D" in the tables.

Estimates - Data in CFS tables reflect survey estimates, that is, these numbers and percentages are estimated totals produced using the sum of weighted shipment data (reported or imputed). CFS respondents provided data for a sample of shipments made by their respective establishments in the survey year. For each establishment, an estimate of that establishment's total value of shipments was produced for the entire survey year. To do this, four different weights were used - the shipment weight, the shipment nonresponse weight, the quarter weight, and the quarter nonresponse weight. Three additional weights were then applied to produce estimates representative of the entire universe - the establishment-level adjustment weight, the establishment (or sample) weight, and the industry-level adjustment weight.

Great Circle Distance - The shortest distance between two points on the surface of a sphere, measured over the surface of that sphere.

Mode of Transportation – The type(s) of transportation used to transport a shipment from its origin to destination.

The modes of transportation were defined as follows:

Single Mode Shipments - Shipments transported by only one of the following modes: Private truck, For-hire truck, Rail, any water mode, Pipeline, or Air.

Multiple Mode Shipments - Shipments for which two or more of the following modes of transportation were used AND Parcel delivery/Courier/U.S. Parcel Post shipments:

Other Mode(s) – Includes shipments with a mode other than any of the listed modes, such as conveyor belt, animal power, etc. 

North American Industry Classification System (NAICS) - The North American Industry Classification System (NAICS) is the standard used by federal statistical agencies in classifying business establishments for the purpose of collecting, analyzing, and publishing statistical data related to the U.S. economy. NAICS was developed under the sponsorship of the Office of Management and Budget (OMB), and adopted in 1997 to replace the Standard Industrial Classification (SIC) system. NAICS groups industries into 20 broad sectors (as opposed to 10 sectors under SIC), identified by a 6-digit code (SIC had a 4-digit code) and is based on the type of the establishment, not the type of commodity. The SIC was used in conducting the 1993 and 1997 CFS; however, the 2002, 2007, 2012, and 2017 CFS used the NAICS. [Note: NAICS is a hierarchical classification system. A 2-digit NAICS code identifies an industry sector, the 3rd digit identifies the subsector, the 4th digit designates the industry group, and the 6-digit code indentifies a specific industry.  See NAICS for more information.]

Sampling Error - Because CFS estimates are produced from a sample survey (as opposed to a complete enumeration of all shipments from all establishments,) a measure of sampling error is likewise estimated and provided for all estimates shown in tables. Common measures related to sampling error are the sampling variance, the standard error, and the coefficient of variation (CV). The sampling variance is the squared difference, averaged over all possible samples of the same size and design, between the estimator and its average value. The standard error is the square root of the sampling variance. The CV expresses the standard error as a percentage of the estimate to which it refers. In the CFS tables, we use CVs to express the sampling error of estimates for shipment characteristics (values, tons, ton-miles, and average miles per shipment) whereas standard errors are provided for percentages (where calculated).

Shipment - A shipment is a single movement of goods, commodities, or products from an establishment to a customer or to another establishment owned or operated by the same company as the originating establishment (e.g., a warehouse, distribution center, or retail or wholesale outlet). Full or partial truckloads are counted as a single shipment only if all commodities on the truck are destined for the same location. If a truck makes multiple deliveries on a route, the goods delivered at each stop are counted as one shipment. Interoffice memos, payroll checks, or business correspondence are not considered shipments. Shipments such as refuse, scrap paper, waste, or recyclable materials are not considered shipments unless the establishment is in the business of selling or providing these materials.

Standard Classification of Transported Goods (SCTG) - The commodities shown in this report are classified using the SCTG coding system. The SCTG coding system was developed jointly by agencies of the United States and Canadian governments based on the Harmonized Commodity Description and Coding System (Harmonized System) to address statistical needs in regard to products transported. The SCTG employs a five-digit numbering system, the structure of which is hierarchical consisting of four levels. (See (link to SCTG site) for more information on the SCTG coding system.) The SCTG system was used in the 1997, 2002, 2007, 2012, and 2017 iterations of the CFS; the Standard Transportation Commodity Code (STCC) coding scheme maintained by the Association of American Railroads was used in the initial CFS (1993).

Temperature Control – A temperature controlled shipment is defined as a shipment that is transported in a vehicle or container that regulates the temperature while en route (such as heating and refrigeration) or maintaining the temperature of the commodity at the time of loading (such as insulation). This excludes shipments of commodities that have temperature sensitivity without a means of controlling the temperature in the vehicle or container while in transport.

Ton-Miles - The shipment weight multiplied by the mileage traveled by the shipment.  For example, the ton-miles for a shipment weighing 3 tons and transported 2 miles is calculated as: 3 x 2 = 6 Ton-miles. The respondents reported shipment weight in pounds. Aggregated pound-miles were converted to ton-miles. Mileage was calculated as the distance between the shipment origin and destination ZIP Codes. For shipments over the surface of the earth, those by truck, rail, and water, the mileage excludes international segments. For example, mileages from Alaska to the continental United States exclude any mileages through Canada (see "Mileage Calculation” for more details). Ton-miles estimates are displayed in millions.

Tons Shipped - The total weight of the entire shipment. Respondents reported the weight in pounds. Aggregated pounds were converted to short-tons (2,000 pounds). The ton totals in the CFS represent the sum of separate shipments of a commodity as it moves through the production and consumption segments of the supply chain; hence the tonnage of goods may be counted more than once in the production life cycle (e.g., goods that are moved through distribution centers).

Total Modal Activity (see CFS Table 2) - Refers to the values for the overall activity (e.g., ton-miles) of a specific mode of transportation. It includes shipments made with a particular mode, whether used as single-mode shipment, or as part of a multiple-mode shipment. For example, the total modal activity for Private truck is the total ton-miles carried by Private truck in single-mode shipments, combined with the total ton-miles carried by Private truck in all multiple-mode shipments that include Private truck (Private truck and Rail, Private truck and Air, Private truck and Inland water, etc.)

Value of Shipments - The dollar value of the entire shipment.  This was defined as the net selling value, exclusive of freight charges and excise taxes. The value data are displayed in millions of dollars. The total value of shipments, as measured by the CFS, and the U.S. Gross Domestic Product (GDP) provide different measures of economic activity and are not directly comparable.  Three important differences can be identified between GDP and value of shipments:

1. GDP captures goods and services produced by all establishments located in the United States, while the CFS measures goods shipped from a subset of establishments.
2. GDP measures the value of goods produced and of services performed. CFS measures the value of goods shipped.
3. GDP counts only the value-added at each step in the production of a product. CFS captures the value of materials used in the production or manufacturing of a product, as well as the value of the finished product itself.  This means that the value of a commodity captured in the CFS may be recorded multiple times during its distribution cycle.