Louisville Exploration Company reported these figures for 2016 and 2015:

Compute rate of return on common stockholders€™ equity for 2016 assuming no dividends were paid to preferred stockholders.

2016 2015 Income Statement-partial: Net Income Balance Sheet-partial: $ 15,500,000 18,800,000 Total Assets Preferred Stock Common Stock Retained Earnings Total Stockholders' Equity Dec. 31, 2016 324,000,000 2,600,000 180,000,000 7,000,000 189,600,000 Dec. 31, 2015 316,000,000 2,600,000 171,000,000 5,500,000 179,100,000