Segments

Our operating segments are defined as components of the enterprise for which separate financial information is available and evaluated on a regular basis by our chief operating decision maker to allocate resources and assess performance.

For purposes of measuring business segment performance, the Company utilizes segment operating income, which is defined as revenues less expenses identifiable to the product lines within each segment. The Company does not allocate items that are non-operating; unusual in nature; or are corporate costs, which include but are not limited to executive and share-based compensation and corporate office costs. Segment operating income reconciles to consolidated income before income taxes by deducting corporate costs; certain non-cash and/or non-operating items; Other components of pension income and other postretirement benefits expense, net; and interest expense.

Results by business segment were as follows:



	Three Months Ended March 31,
	2019			2018
	(In millions)
Net sales:
Supply Technologies	$	165.3		$	160.9
Assembly Components	138.3			145.4
Engineered Products	116.5			99.4
	$	420.1		$	405.7
Segment operating income:
Supply Technologies	$	13.1		$	12.5
Assembly Components	8.3			12.6
Engineered Products	8.1			5.7
Total segment operating income	29.5			30.8
Corporate costs	(7.0		)	(8.7		)
Operating income	22.5			22.1
Other components of pension income and other postretirement benefits expense, net	1.3			2.3
Interest expense, net	(8.2		)	(8.4		)
Income before income taxes	$	15.6		$	16.0