Consider the return on equity, expressed like an interest rate in percentage points per year, for a sample of companies:
5.5, 10.6, 19.0, 24.5, 6.6, 26.8, 6.2, –2.4, –28.3, 2.3
a. Find the average and standard deviation of the return on equity.
b. Interpret the standard deviation.
c. How many standard deviations below average is the worst performance?
d. Draw a histogram and indicate the average, the standard deviation, and the deviation of the worst performance.