Jodie Foster Care Homes, Incorporated shows the following data:

Year    Net Income    Total Assets    Stockholders' Equity      Total Debt
2012        $118,000       $1,900,000        $700,000               $1,200,000
2013         131,000        1,950,000          950,000                1,000,000
2014         148,000        2,010,000         1,100,000               910,000
2015         175,700        2,050,000         1,420,000               630,000

a. Compare the ratio of net income to total assets for each year and comment on the trend.

b. Compute the ratio of net income to stockholders' equity and comment on the trend. Explain why there may be a difference in the trends between parts a and b.