Change in Productivity as the Primary Determinant of the Income of Agriculture After Poland’s Integration into the European Union

The article aimed to verify the development of the productivity level of Polish agriculture after EU integration as a key determinant of agricultural income. The research in this area was concerted because the productivity of agriculture (its technical efficiency) is a specific measure of its social efficiency, as it determines the level of wealth and social welfare and, at the same time, it is a determinant of its competitiveness in the long term. At the same time, it should be noted that after integration, agricultural production in Poland was carried out under conditions of extensive restrictions resulting from the adopted principles of the common agricultural policy aimed at increasing environmental sustainability. Productivity was measured on individual farm data using the Data Envelopment Analysis (DEA) Slacks-Based Model. The results were then extrapolated to the broader collective of commodity farms in Poland and indirectly applied to the entire population. The obtained results allowed for the conclusion that, during the first years of membership, there was a systematic decrease in productivity, which was observed from 2004 to 2011. The average value of the productivity factor for the research sample decreased from 0.230 to 0.208, while for the population it decreased from 0.224 to 0.202. After then, there was a reversal in the direction of the development trend, and in the following years, an upward trend emerged. Thus, the phenomenon of convergence in agricultural productivity with other EU countries, as the main factor influencing the direction of its changes in Poland after accession to the European Union, was not confirmed. Also, in the post-integration period, there was no change in the expected directions of interaction between the main determinants of agricultural income. Indeed, the theoretically formulated and empirically verified relations between subsidies and price relations and productivity were confirmed. Using the world price index as an explanatory variable in the multiple regression model, it was possible to explain, to a large extent, the variability of the productivity of Polish agriculture. Hence the implication for policymakers is that, despite high levels of subsidisation, the market is the main determinant of productivity changes. The weak impact of the price ratio index in Poland (‘price scissors’) on productivity volatility indicates that the increase in production costs, including those related to environmental protection (sustainability), has been effectively offset.