Using the prices provided, calculate the monthly returns for each of the stocks, where r = (P_t/P_t-1) 1; which is the same as [(P_t-P_t-1)/ P_t-1] . PLEASE NOTE THAT THE DATA IS LISTED FROM JAN 2017 TO JAN 2015! SO BE CAREFUL WITH YOUR RETURN FORMULA!

	MSFT Prices	SPY Prices
Date	Adj Close	Adj Close

1/3/2017	62.202896	225.240005
12/1/2016	61.765545	223.529999
11/1/2016	59.896873	219.088669
10/3/2016	59.159267	211.30455
9/1/2016	56.868721	215.032578
8/1/2016	56.730499	215.020111
7/1/2016	55.613781	214.762924
6/1/2016	50.207428	207.205856
5/2/2016	52.003006	206.488144
4/1/2016	48.59201	203.03421
3/1/2016	53.814655	202.237152
2/1/2016	49.57613	189.490845
1/4/2016	53.295586	189.647491
12/1/2015	53.672882	199.584106
11/2/2015	52.579689	203.094086
10/1/2015	50.584435	202.354446
9/1/2015	42.531666	186.491531
8/3/2015	41.820564	191.374634
7/1/2015	44.582397	203.796036
6/1/2015	42.148026	199.294128
5/1/2015	44.735142	203.426132
4/1/2015	46.134602	200.844055
3/2/2015	38.565643	198.888199
2/2/2015	41.591328	202.061722
1/2/2015	38.048264	191.309265