Response to the following problem:
Common-size and trend percents for Aziz Company's sales, cost of goods sold, and expenses follow. Determine whether net income increased, decreased, or remained unchanged in this three-year period.
Common-Size Percents Trend Percents
2012 2011 2010 2012 2011 2010
Sales . . . . . . . . . . . . . . . . . . . . 100.0% 100.0% 100.0% 104.4% 103.2% 100.0%
Cost of goods sold . . . . . . . . 62.4 60.9 58.1 102.0 108.1 100.0
Total expenses . . . . . . . . . . . . 14.3 13.8 14.1 105.9 101.0 100.0