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Jack L. Runyan
U.S. Department of Agriculture
Research
on farm accidents centers around causes and severity of injuries
and illnesses, health and safety of youth, farm safety education,
and improved survey techniques. Examples of research from
each of these areas are discussed below.
Gerberich
and others point out the need for continued and improved injury
surveillance. "A major barrier to progress in the prevention
of agricultural injuries has been not only a lack of knowledge
about the magnitude of the problem but also a deficiency in
knowledge about the specific causes or risk factors due to the
lack of analytical studies" (Gerberich and others, 1991, p.
161). The status of injuries and illnesses on farms is one of
the first items of information that should be determined. Status
of injury or illness includes information about the victim,
the agent that caused the injury or illness, the task being
performed when the illness or injury occurred, and other information
that will describe the event.
Injuries Injuries
in farming range from cuts and scrapes to total disabilities
and fatalities. Most traumatic injuries occur during interactions
with machinery, especially tractors (Bean, 1991). Injuries also
result from poor building design, electric power, livestock
handling, and weather conditions. The activities that victims
were most often performing when injured are machinery maintenance,
fieldwork, and caring for animals (Hoskin and others, 1988b
and 1988c; Pollock, 1990; and Yoder and others 1989).
Tractors.
Tractor accidents have been identified as the leading cause
of deaths and disabling injuries on farms (National Coalition
for Agricultural Safety and Health, 1988). Tractors are the
most frequent cause (one-third to one-half) of injury for
fatal farm accidents but account for a much smaller percentage
(5 to 10 percent) of nonfatal farm accidents, according to
Murphy (Murphy, 1990). Murphy also reports that the types
of fatal tractor accidents have not changed over the last
0-plus years, with overturn accounting for about one-half
and runover accounting for about one-fourth of such accidents
(Murphy, 1990). The results from a study of tractor fatalities
in New York between 1985 and 1988 by Pollock support Murphy's
findings (Pollock, 1990). Most deaths caused by overturns
and runovers could be prevented if tractors were equipped
with rollover protective structures (ROPS) and seat belts
and if passengers were not allowed on tractors. However, only
about one-third of the tractors on U.S. farms are equipped
with such protective structures (Heffernan, 1991). According
to a study in Pennsylvania, less than 19 percent of the tractors
had ROPS (Huizinga and Murphy, 1988). Other types of fatal
injuries involving tractors are caused by power takeoff (PTO)
entanglements, contact with overhead electrical wires, and
road collisions (Madsen, 1991).
Not
all injuries involving tractors are fatal. Hoskin and others,
in their report on tractor-related injuries, showed that "struck
by or against" an object and fall from a different level were
the most frequent types of injuries. These generally resulted
in bruises or fractures (struck by or against) and fractures
or sprains to the foot (fall) (Hoskin and others, 1988b).
Most of the struck by or against accidents occurred during
fieldwork, but most of the accidents by falls occurred while
t e tractor was parked or stationary (Hoskin and others, 1988b).
In another tractor safety study, Schumacher and others visually
inspected tractors to determine whether tractor owners/operators
were maintaining and using original equipment manufacturers
(OEM) safety devices (Schumacher and others, 1989). This study
drew two conclusions. First, "farm tractor owners/operators
tend to neglect the maintenance of OEM tractor safety devices
as the age of the tractor increases" (Schumacher and others,
1989, p. 5). Second, "in the most general way, a lack of safety
consciousness on the parts of tractor owners/operators was
apparent" ( chumacher and others, p. 5).
Machinery
Other Than Tractors. Hoskin and others in their study
of machinery-related injuries showed that most accidents occurred
when the victim was struck by or struck against the machine
while performing maintenance on combines with grain heads
when the machine was not running (Hoskin and others, 1988a).
Other types of injuries that happen when working with machinery
include entanglements in belts, chains, gears, power takeoffs
at the tractor and along the PTO drive, and crop gathering
and moving mechanisms (Madsen, 1991). Most machinery is manufactured
with protective devices, and warning signs are placed on the
machines at spots where workers can become easily entangled.
Nonmachinery.
Hoskin and others report the most frequent type of nonmachinery-related
injuries is 'struck by or against an object. These injuries
generally result in a bruise or fracture to the head and most
often happen while performing chores involving animals or
treating animals (Hoskin and others, 1988c). A Pennsylvania
study supports these findings, showing that the largest percentage
of farm injuries occurred in barns (30 percent), fields (16
percent), barnyards (14 percent), a d farm buildings (12 percent)
(Huizinga and Murphy, 1988).
Respiratory
Disease. Respiratory diseases are not new to farmers and
farmworkers. In 1713, Bernardino Ramazzini wrote that "measurers
and sifters of grain were at risk for respiratory problems,"
and in 1832, Charles Thackrah "described a relationship between
asthma and inhalation of corn dust" (Von Essen, 1991). In
1974, a study by a small group of veterinary practitioners
showed that respiratory problems appeared in workers exposed
to swine confinement areas (Donham, 1992).
According
to Von Essen, at least six disorders are associated with exposure
to airborne dusts in farming: hypersensitivity pneumonitis
(HP), organic dust toxic syndrome (ODTS), chronic bronchitis
(CB), acute pulmonary symptoms (APS), asthma, and mucous membrane
irritation (MMI) (Von Essen, 1991). HP is caused by exposure
to antigens found in silage and in spoiled hay and grain.
HP is commonly seen on dairy farms but has also been found
on farms where grain is stored in drying bins and is found
in poultry houses and mushroom houses (Von Essen, 1991). ODTS
occurs after exposure to large amounts of organic dust (Von
Essen, 1991). Workers affected by ODTS include those uncapping
silos on dairy farms, cleaning grain bins, moving moldy grain,
and working in swine confinement facilities (Von Essen, 1991).
The precise cause of CB, other than airborne dust, has not
been isolated; nor have the individuals who are at high risk
been identified. However, workers in swine confinement areas,
poultry farmers, and handlers of grain appear to have risks
of suffering from CB (Von Essen, 1991). The occurrence of APS
has been studied in grain farmers and swine confinement workers,
and both groups have exhibited symptoms (Von Essen, 1991).
Asthma can be triggered by many farm antigens. Also, many
farm antigens cause MMI.
In addition
to airborne dusts, some gases can cause acute toxicity. The
primary locations of these gases are silos, manure pits, and
modern semienclosed animal production buildings (Hurst, 1992;
Popendorf, 1991; and Zwemer and others, 1992). Soon after
corn is ensiled, nitrogen oxide levels begin increasing and
continue to increase for about 7 days. Anyone entering silos
during the first 2 weeks after filling may experience difficult
or labored breathing (dyspnea) or, in the extreme case, death (Popendorf, 1991; and Zwemer and others, 1992). Hydrogen
sulphide, methane, ammonia, carbon dioxide, and carbon monoxide
are some of the toxic gases emanating from manure pits, especially
when the manure is being agitated (Hurst, 1992). Even when
the levels of these gases are not high enough to be fatal,
unconsciousness may cause drowning or near drowning in manure
liquids (Hurst, 1992). High levels of ammonia have been documented
in poultry and swine confinement facilities, especially in
winter (Popendorf, 1991). Concentrations of ammonia in these
facilities would ordinarily be only a strong irritant to the
eyes, nose, and throat but when combined with organic dusts
could cause pulmonary damage (Popendorf, 1991).
Cancers.
Leukemia, Hodgkin's disease, non-Hodgkin's lymphoma, multiple
myeloma, and cancers of the lip, skin, stomach, prostate,
and brain have excessive occurrences in farmers (Novello,
1991). The marked frequency of these cancers in farmers have
not been conclusively identified (Blair and Zahm, 1992; McDuffie
and others, 1988; McDuffie and others, 1990; and Novello,
1991). However, "cancers of the skin and lip are linked to
increased exposure to the sun's ultraviolet radiation," an
exposures to nitrates, pesticides, viruses, antigenic stimulants,
and various fuels, oils, and solvents are suspected causes
of many cancers (Novello, 1991; and U.S. Department of Heath
and Human Services, 1991a). Some evidence indicates women
on farms have higher incident rates of multiple myeloma than
do farm men (Zahm and others, 1992a).
Pesticide
Toxicity. Exposure to pesticides can produce acute and
chronic toxic reactions. Acute reactions develop immediately
after moderate or high exposures to pesticides. Symptoms of
acute reactions include dizziness, vomiting, headache, fatigue,
drowsiness, and skin rashes. Although this area of toxicity
is not yet fully scientifically documented, some of the suspected
chronic effects are central nervous system damage, lung diseases,
soft tissue sarcoma, Hodgkin's disease, non-H dgkin's lymphoma,
leukemia, and lung cancer (Blair, 1991; National Coalition
for Agricultural Safety and Health, 1988, and Zahm and others,
1992b). More research on the chronic effects of pesticide
exposures is required.
Dermatitis.
Occupational dermatitis is very common among workers on U.S.
farms (National Coalition for Agricultural Safety and Health,
1988). Among the agents causing dermatitis and related skin
conditions are ammonia fertilizers, animal feed additives,
pesticides, plants, sunlight, cattle, swine, sheep, moist
and hot environments, and chiggers, bees, and wasps (Blair,
1991; Susitaival and others, 1992; Zwemer and others, 1992).
Musculoskeletal
Syndromes. Degenerative musculoskeletal syndromes are
widespread among farmers and farmworkers (National Coalition
for Agricultural Safety and Health, 1988; and Novello, 1991).
Low back pain, hip arthrosis, and degenerative arthritis of
the knee and upper extremities are the syndromes most often
reported (National Coalition for Agricultural Safety and Health,
1988; and Novello, 1991). Chronic vibration from tractors
and farm machinery and repetitive trauma associated with farm
work can lead to musculoskeletal syndromes (Barbieri and others,
1992; Holness and Nethercott, 1992; National Coalition for
Agricultural Safety and Health, 1988; and Novello, 1991).
Noise-induced
Hearing Loss. Another occupational hazard for farmers
and farmworkers is hearing loss caused by exposure to farm
machinery, especially tractors. Hearing losses affect about
a quarter of younger farmers and one-half of older farmers
(May and Dennis, 1992; National Coalition for Agricultural
Safety and Health, 1988; Novello, 1991; and Reesal and others,
1992). "Significant numbers of those affected have been found
to develop a communication handicap by age 30" (National Coalition for Agricultural Safety and Health, 1988, p. 21).
Stress-Related
Mental Disorders. Farmers, farmworkers, and farm family
members have high rates of stress-related mental disorders,
especially depression (Heffernan, 1991). "Some of these disorders
appear to be related to isolation, and others result from
agricultural stressors such as economic hardship and weather
conditions" (National Coalition for Agricultural Safety and
Health, 1988, p. 21). Factors beyond a farmer's control, such
as reduced revenue, increased workload, weather, an management
problems, were found to cause significant mental stress (Crevier
and Brun, 1992).
Youth
present a special problem in the area of farm safety. The Fair
Labor Standards Act limits the employment of minors according
to age and occupational activity (Runyan, 1992).[1]
Some children as young as 10 years old may work on farms with
parental consent. Children of farm operators may work for their
parents on their own farms at any age. In addition, many children
are at risk by living on farms. A study of 169 Iowa farm families
highlights some of the safety issues related to youth:
- more
than 40 percent of the children who operated equipment were
not supervised;
- about
30 percent of children more than 3 years old played alone
in work areas and 80 percent of them played near machinery
in operation; and
- children
began operating equipment at an average age of 12, even
though parents believed their children were not capable
of operating equipment until age 15 (Hawk and others, 1991).
An earlier
study of injuries to farm youth (less than 20 years of age)
in 1979, 1980, and 1981 used national statistics (Reesal and
others, 1992). According to this study,
- about
300 youth die each year from farm injuries and 23,500 suffer
nonfatal injuries;
- rates
of fatal and nonfatal injuries increase with the age of
the victim;
- fatal
and nonfatal injury rates are much higher for males than
for females;
- more
than one-half of the victims of fatal farm injuries die
before reaching a physician, nearly one-fifth die in transit
to a hospital, and about one-tenth live long enough to receive
in-patient care;
- nearly
90 percent of the nonfatal injuries were treated in an emergency
room and released; and
- accidents
involving farm machinery accounted for most of the fatal
and nonfatal injuries, with tractors being involved in more
accidents than other machinery. Other farm machinery involved
in such accidents were wagons and combines. However, these
findings may be somewhat misleading because the data include
deaths due to drowning and firearms and do not distinguish
between recreation and farm-related activities as agents
of death (Rivara, 1985).
A study
of fatal farm-related injuries to children 9 years of age
and under in Wisconsin and Illinois from 1979 to 1985 that
used death certificate data showed the average annual death
rates in the study population were 3.2 per 100,000 in Wisconsin
and 1.5 per 100,000 in Illinois (Saimi and others, 1989).
The study found that the death rate was substantially higher
for boys than for girls, that most fatalities occurred in
July, and that machinery was the source of more than one-half
of the injuries in Wisconsin and Illinois during the period
of the study (Salmi and others, 1989).
The
most successful education efforts to improve farm safety will
involve farmers, farm family members, farmworkers, educators
(both extension and institutional), researchers, farm equipment
design engineers, and political policy leaders. All of these
groups have a stake in farm safety. A brief review of some literature
on farm safety education follows.
Farmers'
Perceptions of Heath and Safety Issues One of the
first questions to ask when planning an education program is
whether or not the participants realize a problem exists. Research
studies in New York and in Iowa focused on farmers' perceptions
of health and safety issues, accident causes, and methods of
accident prevention (Kendall and others, 1990; and Pollock,
1990). Both studies showed farm families to be aware that farming
is a hazardous occupation and that safety is important even
when this factor is ranked alongside such matters as prices
and the environment. Findings also indicated that farm families
were receptive to receiving constant reminders and literature
about safe working practices, especially when these practices
could be put to use by all ages. Farm magazines, the Cooperative
Extension Service, and local equipment dealers (in the Iowa
study) were found to be the most frequently used sources of
safety information. Farm families participating in the New York
study had reservations that safety meetings might not be the
best way to communicate safety information (Pollock, 1990).
Farm
operators and family members are aware of farming hazards,
but in times of stress, such people may make decisions that
under more ideal conditions would have been considered dangerous
and unwise. For example, a farmer may throw aside a bent power
takeoff shield so that grain unloading can go forward, rather
than wait until the shield can be repaired. In this example,
the operator is unconsciously making the economic decision
that the value of the time required to repair the shield is
greater than the potential loss that might result from an
injury. But, under identical conditions, this same operator
would probably not forget to check the tractor's oil level
or to lubricate the moving parts as required.
Suggested
Methods for Educating About Farm Safety Individuals
concerned with occupational and farm safety issues frequently
ask, "If nonagricultural industries can reduce their death and
injury rates, why can't agriculture?" Aherin and others suggest
that the answer to this question lies in the lack of engineering
research and research funding for agricultural safety. However,
these authors argue that "it is equally important to recognize
that we should not stop trying to do a better job with education
methods" (Aherin and others, 1990, p. 9). The authors suggest
that behavioral psychology may help in providing solutions for
this continuing problem (Aherin, 1991; and Aherin and others,
1990).
Variables
of Effective Safety Communication. Aherin and others identify
several variables of effective safety communication: source
characteristics, social support/conformity, personal involvement,
and characteristics of the message itself. They argue that
the most effective message will be conveyed by one who is
an expert in agricultural issues, is trusted and liked by
farmers, and is as similar as possible to farmers (source
characteristics). Furthermore, they suggest that people comply
more often with persuasive arguments when with others who
have complied also and that attitudes change more when the
message presented is extremely different from the one already
believed by the receiver (social support/conformity). Also,
"any program that requires the direct participation of the
farmers could potentially increase persuasion and safety behavior"
(personal involvement) (Aherin and others, 1990, p. 16).
Elements
for Safety Communications. Aherin and his colleagues also
note the importance of the characteristics of the message.
They identify four elements that should be included in any
safety communication:
- "the
nature of the hazard;
- the
level of seriousness of the hazard;
- how
to practically avoid the hazard; and the potential consequences
of not avoiding the hazard" (Aherin and others, 1990, p.
16).
These
authors use warning signs and labels, a major form of safety
communication by machinery manufacturers, to demonstrate these
four elements. To be effective, labeling of hazardous machinery
parts requires that
- the
users must perceive that a dangerous situation exists,
- the
explanation of the consequences of disregarding the warning
must be memorable to the hearers,
- the
cost of complying with the warning in terms of time or inconvenience
should not exceed the users' willingness to comply, and
- the
example of those who profit by the warning can inspire others
to do the same. In brief, the warning text that accompanies
the label must be explicit and must answer the question,
"Why should I obey?" (Aherin and others, 1990, p. 18).
An Example
of a Safety Education Effort One example
of an effort to educate people about farm safety is a farm safety
audit called "Farm Safety Walkabout," which could be used either
as an individual or as a community activity, and which was developed
at the University of Iowa (Hawk and others, 1992). The audit
has six one-page sections: people, house, farmyard, farm and
livestock buildings, machinery, and evaluation (of the audit).
The handbook provides all the materials necessary to carry out
a community activity as well as the safety audit, a farm family
health and safety community survey, a pretest to gather information
on safety practices, a post-test to evaluate the effect of the
program, a resource list, an accident emergency information
sheet, and a basic list of supplies for a well-equipped emergency
first-aid kit for a rural home. Gogerty's report gives an evaluation
of the usefulness of this audit (Gogerty, 1991).
Much
of the research published during the past few years concerning
farm safety has either focused on survey methods or devoted
a section to survey methods. Two survey methods are used most
frequently to collect farm accident data: surveys of farm households
and surveys of death certificates.
Farm
Household Surveys The following
discussion includes a survey that was methodologically sound
but had implementation problems and a survey that is being tested.
Standard
Farm Accident Survey Program. In the late 1960's, extension
safety leaders at Ohio State and Michigan State Universities
developed a standardized method of collecting agricultural
accident data (Baker and others, 1990). Using the Ohio State-Michigan
State research as a basis, the National Safety Council, in
cooperation with the U.S. Department of Agriculture, developed
and implemented the Standard Farm Accident Survey Program
(Baker and others, 1990). Although the Standard Farm Accident
Survey Program was methodologically sound, consistent implementation
from State to State was difficult because the survey relied
heavily on volunteers to collect the data and because selecting
and maintaining a stratified sample proved to be difficult
(Baker and others, 1990). Also, some States did not participate
in the study, which limited its usefulness as a national data
source. For these and other reasons, this survey was not conducted
after 1984 (Murphy and Huizinga, 1989).
Modified
Total Design Method. In 1988, a new method for collecting
farm accident data was tested in Pennsylvania through a cooperative
effort involving Pennsylvania State University, the National
Safety Council's Agriculture Division, and the National Institute
for Occupational Safety and Health. This new survey used a
modified Total Design Method (TDM) of a personalized mail
survey (Baker and others, 1990; Murphy and Huizinga, 1989;
and Pollock, 1990)."[2] The survey was
based on a random stratified sample from the most up-to-date
mailing list of farm operators in the State; stratification
variables were type, size, and geographic location of the
farm. Although mail surveys frequently have low response rates
of 25-30 percent, the Pennsylvania survey had a response rate
of 76 percent (Baker and others, 1990; Huizinga and Murphy,
1988; and Murphy and Huizinga, 1989).
During
1989, four more States (Illinois, Missouri, Oregon, and West
Virginia) joined the cooperative effort to test the TDM survey
technique (Pollock, 1990). Researchers in four other States
(Delaware, Indiana, New York, and Ohio) independently used
the TDM survey technique. The States conducting the survey
in 1989 and the respective response rates were Illinois (85
percent), Missouri (57 percent), New York (56 percent), Oregon
(82 percent), West Virginia (57 percent) (Baker and others,
1990 and Pollock, 1990).[3] Based on the surveys in 1988 and 1989, the survey was economical,
averaging about $7.50 per response (Baker and others, 1990).
The goal now is to pool the data from the various States and
to evaluate TDM as a national data collection technique.
Baker
and others indicate two shortcomings of the survey: it does
not allow for in-depth analysis of all accidents, and ft does
not discover many fatal accidents (Baker and others, 1990).
Two changes that may help are Dillman's adaptation of the
TDM for telephone surveys, which would gather more detailed
national accident data, and the improvements suggested by
Murphy, which rely on death certificate data (Murphy, 1989).
The telephone survey will allow for in-depth analysis but
will increase the cost of the survey. Suggested improvements
to make death certificates a more accurate and useful method
for obtaining farm fatality data (as discussed below) will
require some institutional changes that may come about slowly.
Surveys
of Death Certificates In a paper
presented in 1989, Murphy made the point that "quantifying agricultural
occupational fatalities is anything but an exact science," (Murphy,
1989, p. 1). The death certificate, the primary resource used
for documenting these fatalities, contains inaccurate and incomplete
occupation and industry information (Gerberich and others, 1991;
and Murphy, 1989). To help improve occupation and industry data,
Murphy suggests that officials use The Standard Industrial Classification
Manual /I>(SIC code) and the guidelines provided by the National
Center for Heath Statistics to help complete the industry and
occupation spaces on death certificates (Murphy, 1989). In addition
to these resources, he also suggests obtaining relevant information
from a family member of the victim (Murphy, 1989). This information,
once properly collected, can be presented by industry sector
group as well as by industry total and also compared with fatality
data from other major industries (Murphy, 1989).
Other
Suggestions To Improve Surveys
As the following
discussion indicates, more than survey methodology is required
to accurately capture farm accident data.
Classifying
Farm Accidents. Farm safety research has been inconsistent
in identifying accidents that are work related as distinct
from those that are not. Purschwitz and Field discuss the
need for consistency in the definition of a farm accident
and present in a report of 1989 a set of decision rules for
classifying farm accidents as work-related, recreational,
home-related, or other (Purschwitz and Field, 1989).
Standardized
Categories. Research on tractor accidents highlights problems
of classifying data (Murphy, 1990). Murphy notes that most
of the tractor accident data collected over the past 20 years
have not "progressed beyond simple descriptors, (Murphy, 1990,
p. 3)."[4] These descriptors give few
clues as to how to hasten reduction of tractor accidents.
Murphy argues for standardized categories for analysis and
consistent presentation of general descriptive data ( or example,
are farm children persons under 20 years of age, 14 years
and under, or some other age?) and exposure data (hours of
tractor use) (Murphy, 1990). He expands this line of thinking
to include many aspects of farm safety in a subsequent paper
(Murphy, 1991).
Research
in Progress
Studies
of farm accidents are being conducted using the new survey techniques
mentioned earlier in this report. Two of these are discussed
below. In addition, papers presented at the Third International
Symposium: Issues in Heath, Safety and Agriculture and the Surgeon
General's Conference on Agricultural Safety and Heath discuss
research in progress on a broad range of topics (Centre for
Agricultural Medicine, 1992; and U.S. Department of Health and
Human Services, 1991 b). Eight-State
Study. A NIOSH-sponsored study by John Myers analyzed
data on farm injuries in Delaware, Illinois, Indiana, Missouri,
New York, Ohio, Oregon, and West Virginia. A paper summarizing
the farm injuries in these States has been submitted to the
American Journal of Public Health. The paper includes injury
incident rates and a discussion of the data-gathering technique.
A second paper is being prepared from the tractor exposure
data gathered during the study.
University
of Minnesota Study. In 1991, a study of farm accidents
in Minnesota, Nebraska, North Dakota, South Dakota, and Wisconsin
was conducted by the University of Minnesota under a grant
from the Centers for Disease Control (Gerberich and others,
1991). Data for this study were obtained through two telephone
interviews per sample unit. The interviews were 6 months apart,
and each resulted in about 4,000 completed interviews. Results
of this study are not yet available.
Endnotes:
- See appendix for summary of the minimum age requirements of the Fair Labor Standards Act.
- Total Design Method, developed by Don A. Diliman (Dillman, 1978), consists of two parts. First, the researcher must identify each aspect of the survey that may affect quantity and quality of the survey. This includes personalizing all aspects of the survey such as cover letters, survey instruments, and envelopes. Second, the survey should be organized so that design intentions are carried out in complete detail. There should be no monetary cost to the respondent, the survey instrument must be attractively designed, and the relevance of questions should be obvious to the participants (Baker and others, 1990, p. 4).
- Data were not available from Delaware, Indiana, and Ohio.
- Descriptors refer to variables such as the age and sex of the victim, the time of year of the accident, severity of the accident, and the general use of the tractor at the time of the accident.
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NASD Review: 04/2002
This
document was extracted from Bibliographies and Literature of
Agriculture, No. 125, a series of the United States Department
of Agriculture, Economic Research Service, 1301 New York Avenue,
NW, Washington, DC 20005-4788. Publication date: October 1993.
Jack
L. Runyan, Agriculture and Rural Economy Division, Economic
Research Service, U.S. Department of Agriculture, 1301 New
York Avenue, NW. Washington, DC 20005-4788.
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