On January 1, 2014, a company has assets of $15.70 billion and stockholders' equity of $8.30 billion. On January 1, 2015, the same company has assets of $19.70 billion and stockholders' equity of $9.30 billion. During 2014, the company had total sales revenue of $9.30 billion and total expenses of $6.70 billion. The company's asset turnover ratio for 2014 is: