A computer program is described that calculates the cost of the product from a process facility when the capital investment, operating costs, interest rates, tax rates, by-product values, and similar related information are supplied by the user. The program uses a procedure that is mathematically consistent with the discounted cash flow method, and produces a table showing the cash flow history of the project. Considerable flexibility is afforded in the choice of capital structure, depreciation method, and the handling of taxes. Provision is made for parametric studies in which the cost of the feedstock and the annual after-tax rate of return on equity are varied automatically over any desired range. The program can also be used to determine the rate of return on equity when the selling price of the product is supplied by the user. A Fortran listing of the computer program and the results of example problems for coal liquefaction plants are included.