Informal Income Estimation in Iranian Manufacture Industries

Informal income and pseudo financial statements are formed to tax evasion. In the model, informal sales are a function of company’s real and formal profit. The statistical distribution of corporate profit is a specific beta distribution which is called pert. The reason for selecting manufacture industries in this research is the complex process of converting input into output in these firms which makes it difficult to accurately audit the tax. Hence, the creation of informal sales in these firms seems possible. Parameters of probability density function for the profit ratio were calculated by a sample of Tehran stock member manufactures. The results of the study indicate that the informal income ratio at the 99% confidence level is between 11 to 12 percent of total revenues of the firms studied. JEL Classification:  H26, C15, L52