The attached file contains hypothetical data for working this problem. Goodman Corporations and Landry Incorporateds stock prices and dividends, along with the Market Index, are shown in the file. Stock prices are reported for December 31 of each year, and dividends reflect those paid during the year. The market data are adjusted to include dividends.

Data as given in the problem are shown below:
	Goodman Industries		Landry Incorporated		Market Index
Year	Stock Price	Dividend	Stock Price	Dividend	Includes Divs.
2020	$30.32	$2.23	$85.12	$3.52	18,475.97
2019	$23.53	$2.65	$79.32	$3.65	12,174.55
2018	$28.61	$2.73	$74.32	$3.45	12,019.97
2017	$15.21	$2.57	$87.12	$3.47	10,743.05
2016	$12.63	$2.23	$95.12	$3.55	9,455.42
2015	$13.21	$2.25	$84.25	$3.25	8,163.96

b. Calculate the standard deviation of the returns for Goodman, Landry, and the Market Index. (Hint: Use the sample standard deviation formula given in the chapter, which corresponds to the STDEV function in Excel.)
Use the function wizard to calculate the standard deviations.
		Goodman	Landry	Index
Standard deviation of returns