Closing Market Price and NAV History

Date	Market Price1	Net Asset Value2	Bid/Ask Midpoint	Volume1	Net Assets2
6/29/2018	$56.27	$56.22	$56.27	135,455	$1,954,065,972
6/28/2018	$56.12	$56.11	$56.11	81,156	$1,950,096,829
6/27/2018	$55.48	$55.44	$55.49	211,208	$1,926,847,537
6/26/2018	$56.68	$56.67	$56.68	110,578	$1,969,569,561
6/25/2018	$56.38	$56.35	$56.39	126,183	$1,958,495,592
6/22/2018	$57.88	$57.88	$57.89	206,195	$2,005,918,447
6/21/2018	$58.70	$58.70	$58.72	86,236	$2,034,296,547
6/20/2018	$59.29	$59.29	$59.29	96,929	$2,048,626,580
6/19/2018	$59.10	$59.09	$59.10	132,347	$2,041,902,415
6/18/2018	$59.59	$59.57	$59.58	64,471	$2,055,533,113
6/15/2018	$59.52	$59.50	$59.49	108,445	$2,053,055,942
6/14/2018	$59.64	$59.62	$59.62	71,823	$2,057,121,112
6/13/2018	$59.19	$59.18	$59.20	158,993	$2,042,125,577
6/12/2018	$59.13	$59.11	$59.11	149,011	$2,030,819,419
6/11/2018	$58.57	$58.55	$58.58	65,313	$2,011,545,456
6/8/2018	$58.53	$58.51	$58.51	108,352	$2,010,168,397
6/7/2018	$58.24	$58.25	$58.25	303,117	$2,001,109,289
6/6/2018	$59.32	$59.31	$59.21	108,499	$2,031,833,485
6/5/2018	$59.03	$59.02	$59.04	43,000	$2,012,822,748
6/4/2018	$58.56	$58.55	$58.56	144,522	$1,990,981,035
6/1/2018	$58.06	$58.05	$58.04	174,176	$1,971,110,945