Measuring Consolidation in Livestock Farms with the Share-Weighted Size Index

This paper examines consolidation trends in U.S. livestock agriculture using the Share Weighted Size Index (SWSI), a distribution-sensitive measure of structural change. Using publicly available data from the Census of Agriculture (1997 - 2022), we construct SWSI values across three dimensions of farm size - acreage operated, inventory (headcount), and sales - for cattle, dairy, hogs, and poultry (layers and broilers). Results reveal substantial variation in consolidation patterns by commodity and measurement approach. Broiler and hog sectors show high and increasing consolidation in sales and inventory, consistent with vertically integrated and capital-intensive production systems. Dairy exhibits pronounced consolidation in acreage and sales, reflecting industry-wide shifts toward large-scale operations. In contrast, beef cattle operations remain relatively stable over time, with higher consolidation in land use than in sales or inventory. The SWSI provides a more nuanced and transparent measure than average farm size or operation counts, enabling replicable analysis of structural change overtime. By applying the SWSI across multiple livestock commodities and measurement dimensions, this paper highlights the important variation in the pace and form of consolidation, underscoring the value of flexible, commodity-specific tools for understanding structural change in U.S. agriculture.