CHAPTER 1
Available Statistics
The National Agricultural Statistics Service (NASS) of
the U.S. Department of Agriculture (USDA) collects and
publishes official statistics for the U.S. livestock, poultry,
and aquaculture populations. These statistics are based on
the Census of Agriculture conducted every 5 years (e.g.,
1997 and 2002) and surveys conducted monthly, quarterly,
or annually as determined by the particular commodity.
Frequency of surveys and sample sizes by commodity are
shown in appendix 1 (table A1.1).
The Census of Agriculture, which is a complete
enumeration of the entire agricultural segment of the
economy, is the only source of detailed, county-level data
of all farms and ranches in all 50 States selling or intending
to sell agricultural products worth $1,000 or more in
a year. The most recent Census data were collected
for 2002 and published in spring 2004. The U.S. maps
presented in this chapter are based on the 2002 Census
of Agriculture, which provides animal inventory levels as of
December 31, 2002.
In NASS’ ongoing sample survey and estimation
programs, data are collected and estimates are published
within the same month to provide users with the most
up-to-date and timely information—even in the years
the Census is conducted. The massive data-collecting,
editing, and summarizing effort required to prepare the
Census naturally results in a publication lag. Consequently,
sample survey estimates and final Census reports rarely
show exactly the same numbers. These ongoing sample
surveys provide the most up-to-date statistics between
the Census years and are themselves subject to revision
when current-year estimates are made. This is why, if you
compare statistics that we printed in the 2004 animal
health report for 2004 with statistics published in this
year’s version of the report for 2004, the numbers do
not always match. In fact, after each 5-year Census of
Agriculture, NASS reviews all of the previous 5 years’
worth of sample survey estimates, revises the