The graph provides a good approximation of the number of food stamp recipients (in millions) from 1994 through 2004. Use the given ordered pairs to find the average rate of change in food stamp recipients per year during this period. (1994, 27.7) and (2004, 22.7)

Step 1 ：Given two points (1994, 27.7) and (2004, 22.7) which represent the number of food stamp recipients (in millions) in the years 1994 and 2004 respectively.

Step 2 ：The average rate of change is calculated by taking the difference in the y-values (number of food stamp recipients) and dividing by the difference in the x-values (years). This is essentially the slope of the line connecting the two points.

Step 3 ：Subtract the y-values: 22.7 - 27.7 = -5

Step 4 ：Subtract the x-values: 2004 - 1994 = 10

Step 5 ：Divide the difference in y-values by the difference in x-values: -5 / 10 = -0.5

Step 6 ：\(\boxed{-0.5}\) is the average rate of change in food stamp recipients per year during this period.