Sources of growth in Illinois grain production: 1938-1976
1978
Swanson, E.R.
The period 1938-1976 was divided into two equal periods for analysis. A grain production index indicated that in the earlier half of this period, grain production in Illinois increased at an annual compound rate of 2.80 percent, compared to 3.38 percent in the second half. The relative importance of each of the following four components of grain production increase were estimated--the acreage in grain crops, grain crop yields, cropping pattern or crop mix, and the interaction between yields and cropping patterns. Increases in area in grain crops were about half as important as yield increases in the first half of the period, but dropped to about a third of the influence compared to yields in the second half of the period.
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