What is the Annual County Data Program?
The end-of-season December survey is supplemented with a mailing to a county sample of about 300,000 farm operators (~15 percent of the 2.19 million farms) to collect information to support the County Data program. The responses from this supplemental sample are combined with those from the December Quarterly Survey and aggregated to a County Summary.
The county data are "assembled" starting from the State estimate and working back to the county and are published by each NASS Field Office and loaded to the On-Line-Database (Published Estimates or Quick Stats Data Base). The following is a brief outline of the process to produce the annual county data, using corn for grain as an example. The State Corn for Grain estimate, published in the Crop Production Summary each January, is the total to which the counties must add. The County Summary, in combination with administrative data from various sources (other USDA agencies, cotton ginners, etc.), is the basis for the annual county data for crop acreage, yield and production, and livestock inventories. Agricultural Statistics Districts are defined groupings of counties in each State, by geography, climate, and cropping practices. Agricultural Statistics District (ASD) totals are set first because the greatest data accuracy occurs with a larger number of reports. The sum of the ASD's must equal the State estimate. After the ASD's are set, the county values in each district are set. The counties in each district must sum to the district total.
Last modified: 06/02/09