Question: 2.5. A useful measure of a stock's profitability is its yield, defined to be its dividends for 1 the previous 12 months times 100, divided by its current market value. The following table gives the yields of the New York Stock Exchange Common Stock Index for each quarter of the years 1981 through 1985. Are yields affected by the quarter of the year? Is the variability in the yield from year to year statistically significant? State your conclusions using a = 0.05 level of significance.