Optimal agricultural policy and PSE measurement: an assessment and application to Norway

The producer support estimate calculated by the OECD is widely misused as an indicator of distortions created by agricultural policies. In this paper we demonstrate rigorously that a change in the relative (percentage) PSE is not an accurate indicator of the implications of policy reform for domestic welfare or for trade distortions. If there are positive externalities linked to agricultural inputs (e.g., land), we demonstrate that replacing output subsidies by optimal Pigouvian subsidies may result in an increase or a reduction in relative PSE depending on the parameters of the production function. Using the example of Norway we show that an increase in the relative PSE is likely if the focus of agricultural policies shifts from income support to the provision of public goods.