Calculate the average return and standard deviation of this portfolio whose annual returns for a 20-year period are shown below:

Year Return 1 57.38%

2 25.48%

3 23.46%

4 43.46%

5 39.88%

6 13.88%

7 28.01%

8 39.67%

9 -6.67%

10 24.66%

11 6.85%

12 -9.30%

13 22.87%

14 10.18%

15 -21.56%

16 44.63%

17 23.35%

18 20.98%

19 3.11%

20 34.46%

(Note to Chegg Expert: Please show your work so that I understand how to solve this)