The Producer Support Estimate's (PSE's) together with a production and demand model for agricultural products are used to quantify the impact of some policy instruments. The foregoing analysis was done in the context of the work to obtain the Policy Evaluation Matrix (PEM), which integrates support policies to producers - using PSE's - along with a quantitative market effect of such policies, based on elasticity coefficients. This work extends the analysis conducted by OECD - for six member countries- in two dimensions: a temporary one to compute the PEM for the period 2004-2006; and a cross-section analysis that includes Mercosur countries.