Willow Company's balance sheet shows that the beginning balance of stockholders' equity excluding preference shares is $$510,000,$ and the ending balance of stockholder's equity excluding preference shares is $$450,000.$ Willow Company's net profit during the year is $$160,000.$ The company declared a preference dividend of $$40,000.$ Calculate the return on stockholder's equity. $($Provide your answer in percentage and round it to two decimal places.$)$