A) Your portfolio had the values in the following table for the four years listed. There were no withdrawals or contributions of new funds to the portfolio. Calculate your average return over the four-year period.

Year	beginning value	Ending value
2016	60,000	55,000
2017	55,000	65,000
2018	65,000	68,000
2019	68,000	70,000

B) Using your data from Problem 5.1 , calculate the portfolio standard deviation.