Business Segments

We report financial and descriptive information about our reportable operating segments on a basis consistent with that used internally for evaluating segment performance and allocating resources to segments. We evaluate performance primarily on operating income.

We charge management fees and other corporate services to our segments based upon usage or on an overhead allocation basis. Corporate and other operating losses represent operating expenses of YRC Worldwide, the parent company, including compensation and benefits and professional services for all periods presented. Corporate identifiable assets primarily refer to cash, cash equivalents, restricted cash and deferred debt issuance costs and our investment in JHJ until March 2016. Intersegment revenue relates to transportation services between our segments.

Revenue from foreign sources totaled $99.3 million, $101.0 million, and $116.5 million for the years ended December 31, 2017, 2016, and 2015, respectively, and is mainly derived from Canada and, to a lesser extent, Mexico. Long-lived assets located in foreign countries totaled $5.3 million, $5.2 million and $6.5 million at December 31, 2017, 2016, and 2015, respectively.

The following table summarizes our operations by business segment:



(in millions)	YRC Freight			Regional Transportation			Corporate/Eliminations			Consolidated
2017
External revenue	$	3,067.9		$	1,823.4		$	(0.3	)	$	4,891.0
Operating income (loss)	41.4			67.9			(10.9		)	98.4
Identifiable assets	1,042.1			607.4			(64.0		)	1,585.5
Acquisition of property and equipment	(66.6		)	(36.6		)	(0.1		)	(103.3		)
Proceeds from disposal of property and equipment	8.1			0.7			—			8.8
Depreciation and amortization	84.8			62.9			—			147.7
2016
External revenue	$	2,958.9		$	1,739.3		$	(0.7	)	$	4,697.5
Operating income (loss)	53.2			81.3			(10.2		)	124.3
Identifiable assets	1,208.7			642.9			(81.6		)	1,770.0
Acquisition of property and equipment	(73.2		)	(27.4		)	—			(100.6		)
Proceeds from disposal of property and equipment	31.3			3.8			—			35.1
Depreciation and amortization	90.3			69.5			—			159.8
2015
External revenue	$	3,055.7		$	1,776.9		$	(0.2	)	$	4,832.4
Operating income (loss)	18.0			85.4			(10.4		)	93.0
Identifiable assets^(a)	1,351.5			652.9			(125.0		)	1,879.4
Acquisition of property and equipment	(59.2		)	(48.7		)	(0.1		)	(108.0		)
Proceeds from disposal of property and equipment	12.0			5.5			—			17.5
Depreciation and amortization	93.1			70.7			(0.1		)	163.7


(a)	Due to the adoption of ASU 2015-03, Interest - Imputation of Interest, “Identifiable assets” were updated for respective years to reflect the reclassification of unamortized debt issuance costs.