SUPERVALU, one of the largest grocery retailers in the United States, is headquartered in Minneapolis. Suppose the following financial information (in millions) was taken from the companys 2017 annual report: net sales $45,400, net income $470, beginning stockholders equity $2,740 and ending stockholders equity $3,025. There were no dividends paid on preferred stock. Compute the return on common stockholders equity. (Round answer to 2 decimal places, e.g. 12.56%.)