외환위기 이후 법인세수 변동요인 분석(A study of the changes in the corporate income tax revenue after the Korean economic crisis)

This paper investigates why the Korean corporation tax has recently raised so much revenue. We examine three economic factors that can affect the corporate income tax(CIT) revenue; including the effective tax rate, profitability, and the total number of firms. Also, to understand the how the CIT revenue depends on the asymmetric performance of different firms, we analyse persistence of firms' profitability as well as the performance of the 100 biggest firms. Our main results show that the increase in the CIT revenue is more closely related to the higher profitability of firms due to the outstanding decreases of firms' debts, rather than the increase in the tax burden of firms(which actually has slightly decreased since the economic crisis). From estimating the transition function of corporate incomes, it turns out that the level(not the relative order) of firms' profitability has become more persistent since the economic crisis. While the tax-payment per firm was stable during the period of 2000 through 2005, the growth rate of the whole CIT revenue(67%) might well be explained by the growth rate of the number of firms(68%), implying the important role of the number of firms in the CIT revenue. However, from the comparison of the increase in the tax payments of the 100 biggest firms(￦8,630bil.) to the increase in the whole CIT revenue(￦8,467bil.), it is inferred that the higher profitability of the 100 biggest firms explains most of the increase in the whole CIT revenue.