Using the data from Jan. 1, 2015 to Dec. 1, 2019, estimate the standard deviation of the monthly returns of a portfolio consisting of one share of KO, one share of T, and one share of XOM. Enter your answer as a percent without the %. Round your final answer to two decimals.

	KO	T	XOM
Date	Adj Close	Adj Close	Adj Close
12/1/14	35.56	25.24	75.13
1/1/15	34.67	24.73	71.04
2/1/15	36.47	26.33	71.95
3/1/15	34.15	24.88	69.60
4/1/15	34.44	26.39	71.54
5/1/15	34.78	26.70	69.76
6/1/15	33.31	27.45	68.69
7/1/15	35.17	26.85	65.39
8/1/15	33.67	26.19	62.11
9/1/15	34.35	25.52	61.95
10/1/15	36.57	26.24	68.94
11/1/15	36.81	26.75	68.04
12/1/15	37.39	27.34	65.52
1/1/16	37.35	28.65	65.44
2/1/16	37.53	29.77	67.37
3/1/16	40.37	31.55	70.90
4/1/16	39.29	31.27	74.98
5/1/16	39.12	31.93	75.50
6/1/16	39.76	35.24	80.18
7/1/16	38.56	35.31	76.08
8/1/16	38.38	33.71	74.53
9/1/16	37.40	33.49	75.29
10/1/16	37.78	30.34	71.87
11/1/16	35.95	32.25	75.30
12/1/16	37.74	33.71	78.55
1/1/17	37.35	35.19	73.00
2/1/17	37.70	35.29	70.77
3/1/17	38.13	35.09	72.02
4/1/17	39.11	33.47	71.70
5/1/17	41.22	32.93	70.69
6/1/17	40.65	32.24	71.57
7/1/17	41.89	33.33	70.95
8/1/17	41.63	32.43	67.66
9/1/17	41.14	33.91	73.38
10/1/17	42.36	29.13	74.60
11/1/17	42.16	31.89	74.55
12/1/17	42.61	34.08	75.56
1/1/18	44.20	32.83	78.86
2/1/18	40.14	32.24	68.42
3/1/18	40.34	31.66	68.09
4/1/18	40.49	29.04	70.95
5/1/18	40.29	29.11	74.14
6/1/18	41.09	28.92	76.26
7/1/18	44.08	28.80	75.14
8/1/18	42.13	29.22	73.90
9/1/18	43.66	30.72	79.18
10/1/18	45.65	28.07	74.21
11/1/18	48.05	29.00	74.04
12/1/18	45.50	26.50	64.15
1/1/19	46.25	27.91	68.94
2/1/19	43.57	29.37	74.35
3/1/19	45.03	29.60	76.86
4/1/19	47.55	29.22	76.36
5/1/19	47.62	29.32	67.32
6/1/19	49.35	32.13	73.73
7/1/19	51.41	32.65	71.54
8/1/19	53.76	34.32	65.89
9/1/19	53.18	36.83	68.78
10/1/19	53.56	37.46	65.82
11/1/19	52.54	36.89	66.37
12/1/19	54.87	38.56	68.79