Stock-based Compensation (Tables)

A summary of total stock-based compensation expense and the related income tax benefits recognized during the three-month periods ended June 30, 2018 and July 1, 2017 is as follows:



	Three Months Ended
	June 30, 2018			July 1, 2017
	(millions)
Compensation expense	$	21.5		$	21.6		^(a)
Income tax benefit	(3.2		)	(7.9		)


^(a)	The three months ended July 1, 2017 includes $2.1 million of accelerated stock-based compensation expense recorded within restructuring and other charges in the consolidated statements of operations (see Note 8). All other stock-based compensation expense was recorded within SG&A expenses.

A summary of stock option activity under all plans during the three months ended June 30, 2018 is as follows:



	Number of Options
	(thousands)
Options outstanding at March 31, 2018	1,151
Granted	—
Exercised	(162	)
Cancelled/Forfeited	(82	)
Options outstanding at June 30, 2018	907

A summary of restricted stock and service-based RSU activity during the three months ended June 30, 2018 is as follows:



	Number of Shares
	Restricted Stock		Service-based RSUs
	(thousands)
Nonvested at March 31, 2018	19		1,072
Granted	—		370
Vested	(9	)	(387	)
Forfeited	—		(62	)
Nonvested at June 30, 2018	10		993

A summary of performance-based RSU activity during the three months ended June 30, 2018 is as follows:



	Number of Performance-based RSUs
	(thousands)
Nonvested at March 31, 2018	1,157
Granted	—
Change due to performance condition achievement	(29	)
Vested	(232	)
Forfeited	(18	)
Nonvested at June 30, 2018	878