Computing and Interpreting Return on Assets and Its Components

McDonald's Corporation (MCD) reported the following balance sheet and income statement data for 2016 through 2018.

$ millions Total Assets Net Income Sales

2018 . . . . . . . . . . . . . . . . . . . . . . . . . . . $32,811.2 $5,924.3 $21,025.2

2017 . . . . . . . . . . . . . . . . . . . . . . . . . . . 33,803.7 5,192.3 22,820.4

2016 . . . . . . . . . . . . . . . . . . . . . . . . . . . 31,023.9

Required

a. What is McDonald's return on assets for 2018 and 2017?

b. Determine the profit margin for 2018 and 2017.

c. Calculate the asset turnover for 2018 and 2017.

d. What factor is mainly responsible for the change in McDonald's ROA over this period? Is it profit margin or asset turnover or both