Evaluation of the Most Important Factors Affecting the Income of Taxes in the Economy of Iran with the Approach of TVP DMA Models

Due to the government’s roles and responsibilities in economy for financing public services through taxes as sustainable revenue, this study investigates not only the effective factors on tax revenues and its theoretical bases but also selects the related important effective variables in Iran’s economy during the period (1971-2017) by using dynamic models TVP - DMA. The classic models focus on the correlations between independent variables and dependent variables in the aforesaid period. The TVP – DMA models have the ability to investigate the correlation between independent variables and dependent variables in each year of that period. The superiority of this model to other econometric models is due to the possibility of changing input variables and changing the variables coefficients through the time. According to the outputs of the models TVP-DMA and TVP-DMS, the results indicate that Iran’s economy variables such as the economy openness, infrastructure budget growth, inflation, average tax rate and the growth of real revenues are the most important effective variables on the direct taxes revenue growth respectively and the variables such as real revenues growth, infrastructure budget growth, inflation, under economy size, informal market currency rate and the ratio of services sector value added to GDP are the most effective variables on indirect tax revenues respectively.