A stock was trading at $117.40 at the end of year 1. It was trading at the end of year 2 at $110.70 immediately after giving a dividend of $3.60. At the end of year 3. it was trading at $120.90 immediately after giving a dividend of $3.80. Finally, it was trading at $131.00 at the end of year 4 without giving out any dividend. What was the arithmetic average annual return of this stock for the three years between years 1 and 4?