Examining irrigation productivity in U.S. agriculture using a single-factor approach

Typical single-factor productivity measures are easy to grasp and to develop but are misleading because they ignore other inputs used in the production process. This study develops a single-factor productivity approach that accounts for conventional inputs as well as observed and unobserved characteristics of the production environment. We then apply this approach to evaluate irrigation productivity in U.S. agriculture using U.S. Department of Agriculture input-output data alongside state-level estimates of volumetric measures of irrigation water withdrawals obtained from the U.S. Geological Survey. An irrigation productivity index is constructed and subsequently decomposed in order to capture irrigation productivity growth due to technological progress, input (factor) deepening, output-oriented scale-and-mix efficiency, output-oriented technical efficiency, and environmental effects. In addition, we evaluate spatial patterns of irrigation productivity across the United States. Our findings indicate that, on average, irrigation productivity has risen modestly in most states, and this growth has primarily been driven by technological progress and input (factor) deepening.