Benefit Plans

The components of net periodic benefit cost for the three months ended March 31 were as follows ($ in millions):



	Pension benefits						Other retirement benefits						Total
	2017			2016			2017			2016			2017			2016
Service cost	$	2.7		$	2.7		$	—		$	0.1		$	2.7		$	2.8
Interest cost	2.5			2.6			0.1			0.1			2.6			2.7
Expected return on assets	(3.4		)	(3.2		)	—			—			(3.4		)	(3.2		)
Amortization of prior service credit	(0.3		)	(0.3		)	(0.2		)	—			(0.5		)	(0.3		)
Recognized actuarial losses (gains)	1.2			1.1			(0.7		)	(0.3		)	0.5			0.8
Net periodic benefit cost	$	2.7		$	2.9		$	(0.8	)	$	(0.1	)	$	1.9		$	2.8

During the three months ended March 31, 2017, we contributed $20.0 million to our U.S. qualified pension plan.