Question

Below are returns on the stock A and S&P500 index. All numbers are in decimals (-0.0222 is equivalent to -2.22%).

A	S_P500
-0.0222	0.0032
-0.0048	-0.0058
0.1333	0.0434
0.0765	0.1081
-0.0161	-0.0121
0.1250	0.1400
0.0145	0.0368
-0.0475	-0.0454
0.0430	0.0577
-0.0260	-0.1374
0.0071	0.0064
0.0249	0.0186
0.0850	0.0215
-0.0624	-0.0752
0.0933	0.0365
0.0456	0.0528
-0.0632	-0.0131
0.0450	0.0009
0.0200	0.0017
0.0280	0.0985

What is the sample standard deviation of the stock A returns?

Please write an answer in decimals. For example, 12.34% would be 0.1234.
Also, round your answer to the fourth decimal.

Your Answer:

Answer 1

	Number of sample	A	(A- Expected return)^2
	1	-0.0222	0.0022
	2	-0.0048	0.0009
	3	0.1333	0.0117
	4	0.0765	0.0027
	5	-0.0161	0.0017
	6	0.125	0.0100
	7	0.0145	0.0001
	8	-0.0475	0.0052
	9	0.043	0.0003
	10	-0.026	0.0026
	11	0.0071	0.0003
	12	0.0249	0.0000
	13	0.085	0.0036
	14	-0.0624	0.0076
	15	0.0933	0.0047
	16	0.0456	0.0004
	17	-0.0632	0.0078
	18	0.045	0.0004
	19	0.02	0.0000
	20	0.028	0.0000
i	Total	0.499	0.0623
ii	Number of observation	20	20
iii=i/ii	Therefore expected return	0.02495
	Variance =	=0.0623/(20-1)		0.003279
	Standard deviation = square root of variance =			0.0573
	Therefore answer =	0.0573