(7) Earnings Per Share Data (“EPS”) and Stock Based Compensation

Basic earnings per share are based on the weighted average number of common shares outstanding during the period. Diluted earnings per share are based on the weighted average number of common shares outstanding during the period adjusted to give effect to common stock equivalents.

The following table sets forth the computation of basic and diluted earnings per share for classes A, B, C and D common stockholders for the periods indicated (in thousands, except per share data):

	Three months ended June 30,						Six months ended June 30,
	2017			2016			2017			2016
Basic and Diluted:
Net income attributable to UHS	$	185,394		$	185,577		$	391,449		$	376,336
Less: Net income attributable to unvested restricted share grants		(82	)		(84	)		(176	)		(173	)
Net income attributable to UHS – basic and diluted	$	185,312		$	185,493		$	391,273		$	376,163

Weighted average number of common shares - basic		96,247			97,109			96,416			97,358
Net effect of dilutive stock options and grants based on the treasury stock method		795			1,280			791			1,284
Weighted average number of common shares and equivalents - diluted		97,042			98,389			97,207			98,642
Earnings per basic share attributable to UHS:	$	1.93		$	1.91		$	4.06		$	3.86
Earnings per diluted share attributable to UHS:	$	1.91		$	1.89		$	4.03		$	3.81

The “Net effect of dilutive stock options and grants based on the treasury stock method”, for all periods presented above, excludes certain outstanding stock options applicable to each period since the effect would have been anti-dilutive. The excluded weighted-average stock options totaled 4.4 million for the six months ended June 30, 2017. The excluded weighted-average stock options totaled 3.0 million for the three months ended June 30, 2017. The excluded weighted-average stock options totaled 2.9 million for the six months ended June 30, 2016. There were no significant anti-dilutive stock options during the three months ended June 30, 2016. All classes of our common stock have the same dividend rights.

Stock-Based Compensation:

During the three-month periods ended June 30, 2017 and 2016, compensation cost of $13.0 million and $10.9 million, respectively, was recognized related to outstanding stock options. During the six-month periods ended June 30, 2017 and 2016, compensation costs of $27.9 million and $23.6 million, respectively, was recognized related to outstanding stock options. In addition, during the three-month periods ended June 30, 2017 and 2016, compensation cost of approximately $448,000 and $340,000, respectively, was recognized related to restricted stock. During the six-month periods ended June 30, 2017 and 2016, compensation cost of approximately $599,000 (net of cancellations) and $659,000, respectively, was recognized related to restricted stock. As of June 30, 2017 there was $124.6 million of unrecognized compensation cost related to unvested options and restricted stock which is expected to be recognized over the remaining weighted average vesting period of 3.0 years. There were 2,980,725 stock options granted (net of cancellations) during the first six months of 2017 with a weighted-average grant date fair value of $27.07 per share.

The expense associated with share-based compensation arrangements is a non-cash charge. In the Condensed Consolidated Statements of Cash Flows, share-based compensation expense is an adjustment to reconcile net income to cash provided by operating activities and aggregated to $29.1 million and $24.7 million during the six-month periods ended June 30, 2017 and 2016, respectively.