In this paper, we calculate the necessary payroll tax to reach the financial equilibrium of the retirement system for formal workers in the private sector in Brazil (INSS). Such an exercise allows us to identify the formal employees who contribute to the increase of the INSS deficit. Although we do not know the subjective value of the benefits provided by INSS for each worker, our intention is to have an idea of the tax (or subsidy) for each contributor, given by the simple difference between the actual and the necessary payroll tax. Using the Brazilian Household Survey (PNAD) for the year 2001, the conclusion is that the necessary payroll tax to balance the system varies within 0.19 and 0.33 percent, depending on the hypotheses about the duration of the contribution; and those related to disability benefits. Finally, we show a great dispersion when we compare taxes among different groups of workers. This result indicates that INSS is a powerful instrument to reduce wage inequality, when transferring resources from groups of a large wage category to those of a lower.