The relevance of corporate investment decisions lies in their impact on shareholder wealth. It not only depends on the investment project but also on the corporate dynamics that turns it into the sequence of shareholders capital contributions, dividends, and gross terminal value that constitutes the shareholders investment project (SIP). We develop a model to calculate the SIP cash flows and the values of its interim capitals following the average internal rate of return (AIRR) paradigm. The shareholders final value depends on two reinvestment rates that, respectively, capture the returns obtained by the retained cash flows and the dividends reinvested by shareholders. On this basis, we approach the analysis of value creation combining both reinvestment rates in the shareholders net present value (SNPV). This model enables us to obtain the AIRR of the SIP and a variant of it, the equity growth rate that embeds the impact of internal and external reinvestment on the shareholders final value. Copyright © 2014 Institute of Industrial Engineers.