Closing Market Price and NAV History

Date	Market Price1	Net Asset Value2	Bid/Ask Midpoint	Volume1	Net Assets2
1/31/2018	$72.73	$72.69	$72.73	49,526	$1,068,587,134
1/30/2018	$73.17	$73.06	$73.08	67,383	$1,073,944,910
1/29/2018	$74.00	$73.98	$74.01	62,312	$1,087,533,462
1/26/2018	$74.54	$74.55	$74.55	47,035	$1,095,933,967
1/25/2018	$73.03	$73.00	$73.01	49,287	$1,073,063,203
1/24/2018	$72.89	$72.86	$72.89	36,876	$1,071,063,071
1/23/2018	$73.08	$73.06	$73.07	60,060	$1,073,927,358
1/22/2018	$72.83	$72.89	$72.91	55,265	$1,067,857,271
1/19/2018	$72.07	$72.07	$72.10	43,392	$1,048,612,753
1/18/2018	$71.32	$71.28	$71.32	58,869	$1,037,111,445
1/17/2018	$71.50	$71.47	$71.49	61,331	$1,039,826,207
1/16/2018	$70.71	$70.69	$70.71	49,972	$1,028,525,016
1/12/2018	$71.22	$71.19	$71.21	52,287	$1,035,752,958
1/11/2018	$70.99	$70.96	$70.99	53,264	$1,032,463,592
1/10/2018	$70.29	$70.24	$70.27	43,082	$1,021,945,598
1/9/2018	$70.41	$70.36	$70.39	108,366	$1,023,674,525
1/8/2018	$70.13	$70.13	$70.15	60,581	$1,013,322,240
1/5/2018	$70.18	$70.18	$70.19	71,645	$1,014,122,153
1/4/2018	$69.53	$69.50	$69.53	52,128	$1,004,281,604
1/3/2018	$69.16	$69.15	$69.13	87,109	$999,190,068
1/2/2018	$68.67	$68.64	$68.67	49,146	$988,470,051