15. SEGMENT AND GEOGRAPHIC INFORMATION

Our business is organized into four business units, each representing a reportable segment under ASC 280 Segment Reporting. The four segments are Driveline, Metal Forming, Powertrain, and Casting. The results of each segment are regularly reviewed by the chief operating decision maker to assess the performance of the segment and make decisions regarding the allocation of resources to the segments.

Our product offerings by segment are as follows:


•	Driveline products consist primarily of axles, driveshafts, power transfer units, rear drive modules, transfer cases, and electric and hybrid driveline products and systems for light trucks, sport utility vehicles (SUVs), crossover vehicles, passenger cars and commercial vehicles;


•	Metal Forming products consist primarily of axle and transmission shafts, ring and pinion gears, differential gears, transmission gears, and suspension components for Original Equipment Manufacturers and Tier 1 automotive suppliers;


•	The Powertrain segment products consist primarily of transmission module and differential assemblies, transmission valve bodies, connecting rod forging and assemblies, torsional vibration dampers, and variable valve timing products for Original Equipment Manufacturers and Tier 1 automotive suppliers; and


•	The Casting segment produces both thin wall castings and high strength ductile iron casting, as well as differential cases, steering knuckles, control arms, brackets, and turbo charger housings for the global light vehicle, commercial and industrial markets.

We use Segment Adjusted EBITDA as the measure of earnings to assess the performance of each segment and determine the resources to be allocated to the segments. Segment Adjusted EBITDA is defined as earnings before interest expense, income taxes, depreciation and amortization for our reportable segments, excluding the impact of restructuring and acquisition-related costs, debt refinancing and redemption costs, gain on the sale of a business, goodwill impairments and non-recurring items.



	Year Ended December 31, 2018

	Driveline		Metal Forming		Powertrain		Casting		Corporate and Eliminations		Total
Sales	$	4,254.8	$	1,515.4	$	1,128.5	$	919.8	$	—	$	7,818.5
Less: Intersegment sales	0.8		418.0		13.8		115.5		—		548.1
Net external sales	$	4,254.0	$	1,097.4	$	1,114.7	$	804.3	$	—	$	7,270.4

Segment adjusted EBITDA	$	660.7	$	285.9	$	163.7	$	73.6	$	—	$	1,183.9

Depreciation and amortization	$	211.7	$	118.6	$	120.9	$	77.6	$	—	$	528.8

Capital Expenditures	$	283.3	$	102.2	$	97.6	$	41.6	$	—	$	524.7

Total Assets	$	2,463.5	$	2,143.1	$	1,679.6	$	664.7	$	559.8	$	7,510.7



	Year Ended December 31, 2017

	Driveline		Metal Forming		Powertrain		Casting		Corporate and Eliminations		Total
Sales	$	4,040.8	$	1,242.6	$	816.5	$	676.4	$	—	$	6,776.3
Less: Intersegment sales	1.1		412.6		9.9		86.7		—		510.3
Net external sales	$	4,039.7	$	830.0	$	806.6	$	589.7	$	—	$	6,266.0

Segment adjusted EBITDA	$	692.3	$	232.3	$	131.1	$	47.0	$	—	$	1,102.7

Depreciation and amortization	$	189.4	$	95.1	$	81.7	$	50.8	$	11.5	$	428.5

Capital Expenditures	$	296.9	$	65.2	$	84.7	$	30.9	$	—	$	477.7

Total Assets	$	2,303.0	$	2,175.3	$	1,824.0	$	984.3	$	596.2	$	7,882.8



	Year Ended December 31, 2016

	Driveline		Metal Forming		Powertrain		Casting		Corporate and Eliminations		Total
Sales	$	3,735.6	$	552.2	$	—	$	—	$	—	$	4,287.8
Less: Intersegment sales	4.9		334.9		—		—		—		339.8
Net external sales	$	3,730.7	$	217.3	$	—	$	—	$	—	$	3,948.0

Segment adjusted EBITDA	$	515.8	$	103.6	$	—	$	—	$	—	$	619.4

Depreciation and amortization	$	160.8	$	24.1	$	—	$	—	$	16.9	$	201.8

Capital Expenditures	$	159.0	$	22.9	$	—	$	—	$	41.1	$	223.0

Total Assets	$	2,183.9	$	410.3	$	—	$	—	$	828.1	$	3,422.3

Assets included in the Corporate and Eliminations column of the tables above represent AAM corporate assets, as well as eliminations of intercompany assets.

The following table represents a reconciliation of Segment Adjusted EBITDA to consolidated income (loss) before income taxes for the years ended December 31, 2018, 2017 and 2016:



	Year Ended December 31,
	2018			2017			2016
Segment adjusted EBITDA	$	1,183.9		$	1,102.7		$	619.4
Interest expense	(216.3		)	(195.6		)	(93.4		)
Depreciation and amortization	(528.8		)	(428.5		)	(201.8		)
Goodwill impairment	(485.5		)	—			—
Restructuring and acquisition-related costs	(78.9		)	(110.7		)	(26.2		)
Pension settlement	—			(3.2		)	—
Gain on sale of business	15.5			—			—
Gain on settlement of capital lease	15.6			—			—
Acquisition-related fair value inventory adjustment	—			(24.9		)	—
Impact of change in accounting principle	—			3.7			—
Debt refinancing and redemption costs	(19.4		)	(3.5		)	—
Other	—			—			1.0
Income (loss) before income taxes	$	(113.9	)	$	340.0		$	299.0

Financial information relating to our operations by geographic area is presented in the following table. Net sales are attributed to countries based upon location of production. We have retrospectively reclassified 2017 and 2016 to present net sales based upon location of production as these amounts were previously presented based upon location of customer. Long-lived assets exclude deferred income taxes.



	December 31,
	2018		2017		2016
	(in millions)
Net sales
United States	$	3,293.2	$	2,742.7	$	1,321.7
Mexico	2,547.1		2,456.1		2,178.7
South America	129.7		133.2		98.2
China	373.4		318.6		137.3
All other Asia	304.9		193.9		128.6
Europe	622.1		421.5		83.5
Total net sales	$	7,270.4	$	6,266.0	$	3,948.0

Long-lived assets
United States	$	3,612.3	$	4,253.8	$	831.0
Mexico	1,117.9		993.8		529.2
South America	70.6		61.4		61.5
China	177.6		180.9		129.8
All other Asia	101.0		103.4		92.0
Europe	356.0		307.4		111.7
Total long-lived assets	$	5,435.4	$	5,900.7	$	1,755.2