
	Year Ended December 31,
	2020			2019			2018
(RSUs in thousands)	RSUs	Weighted- Average Grant Date Fair Value		RSUs	Weighted- Average Grant Date Fair Value		RSUs	Weighted- Average Grant Date Fair Value
Nonvested, beginning of year	1,618	$	165.26	1,522	$	129.96	1,361	$	100.66
Granted(1)	501	$	256.47	843	$	192.37	681	$	163.67
Performance adjustment - awards with market condition(2)	18	$	191.76	12	$	120.96	10	$	78.71
Performance adjustment - awards with performance condition(2)	(10)	$	279.08	62	$	176.89	66	$	162.64
Vested	(742)	$	158.13	(704)	$	125.84	(524)	$	101.38
Forfeited	(62)	$	193.28	(117)	$	140.43	(72)	$	125.29
Nonvested, end of year	1,323	$	201.98	1,618	$	165.26	1,522	$	129.96

(1) Includes all RSUs granted during the year. RSUs with operating performance conditions are issued annually and have one performance cycle or three sub-performance cycles. Performance conditions are assigned near the beginning of each performance cycle or sub-performance cycle, as applicable, and awards are reflected as grants at the target number of units at that time.

(2) RSUs with a market or performance condition are granted at target and vest based on achievement of the market or operating performance and service conditions. The actual number of RSUs issued may be more or less than the target RSUs depending on the achievement of the market or operating performance conditions.

Share-Based Compensation Arrangement By Share-Based Payment Award, Award Type And Vesting Conditions

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Tabular disclosure of allocation of amount expensed and capitalized for award under share-based payment arrangement to statement of income or comprehensive income and statement of financial position. Includes, but is not limited to, corresponding line item in financial statement.

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