Um modelo econométrico com parâmetros variáveis para a carga tributária bruta brasileira trimestral

Abstract

This article estimates a linear econometric model with variable parameters for the analysis of the Brazilian quarterly gross tax burden in the period 1995-2008. The choice of this particular model was motivated by the changes happened in the Brazilian tax system during these years – most frequently in the scope, design, and size of pre-existing taxes, the elimination of some of these taxes and/or the creation of new ones. The main conclusions of the paper are that: i) GDP is, quite certainly, the main explanatory variable of the dynamics of the quarterly tax burden during the period in question; ii) the GDP-elasticity of the Brazilian tax burden appears to have fluctuated around values close to unity; iii) the fraction of the Brazilian tax burden that does not depend on GDP (or on any other variable, for that matter) incre¬ased quite significantly during the most recent years – possibly due to continuous improvements in the ability of the Brazilian government to collect tax revenues and/or the increase in the formal sector of the economy; and finally iv) the model with variable parameters is the most appropriate to deal with this problem considering the criteria adopted.