Our operating segments are as follows: Mineral Fiber, Architectural Specialties and Unallocated Corporate.

Mineral Fiber – produces suspended mineral fiber and soft fiber ceiling systems for use in commercial and residential settings. Products offer various performance attributes such as acoustical control, rated fire protection and aesthetic appeal. Commercial ceiling products are sold to resale distributors and to ceiling systems contractors. Residential ceiling products are sold primarily to wholesalers and retailers (including large home centers). The Mineral Fiber segment also includes the results of WAVE, which manufactures and sells suspension system (grid) products and ceiling component products that are invoiced by both AWI and WAVE. Segment results relating to WAVE consist primarily of equity earnings and reflect our 50% equity interest in the joint venture. Ceiling component products consist of ceiling perimeters and trim, in addition to grid products that support drywall ceiling systems. To a lesser extent, however, in some geographies and for some customers, WAVE sells its suspension systems products to AWI for resale to customers. Mineral Fiber segment results reflect those sales transactions. The Mineral Fiber segment also includes all assets and liabilities not specifically allocated to our Architectural Specialties or Unallocated Corporate segment, including all property and related depreciation associated with our Lancaster, PA headquarters. Operating results for the Mineral Fiber segment include a significant majority of allocated Corporate administrative expenses that represent a reasonable allocation of general services to support its operations.

Architectural Specialties – produces and sources ceilings and walls for use in commercial settings. Products are available in numerous materials, such as metal and wood, in addition to various colors, shapes and designs. Products offer various performance attributes such as acoustical control, rated fire protection and aesthetic appeal. We sell standard and customized products, with the majority of Architectural Specialties revenues derived from sourced products. Architectural Specialties products are sold primarily to resale distributors and ceiling systems contractors. The majority of revenues are project driven, which can lead to more volatile sales patterns due to project scheduling uncertainty. Operating results for the Architectural Specialties segment include a minor portion of allocated Corporate administrative expenses that represent a reasonable allocation of general services to support its operations.

Unallocated Corporate – includes assets, liabilities, income and expenses that have not been allocated to our other business segments and consist of: cash and cash equivalents, the net funded status of our U.S. Retirement Income Plan (“RIP”), the estimated fair value of interest rate swap contracts, outstanding borrowings under our senior credit facility and income tax balances. Our Unallocated Corporate segment also includes all assets, liabilities, income and expenses formerly reported in our EMEA and Pacific Rim segments that were not included in the Sale.

For the year ended 2019	Mineral Fiber			Architectural Specialties		Unallocated Corporate			Total
Net sales to external customers	$	826.6		$	211.5	$	-		$	1,038.1
Equity (earnings) from joint venture		(96.6	)		-		-			(96.6	)
Segment operating income (loss)		289.6			35.9		(8.1	)		317.4
Segment assets		1,139.9			161.8		191.6			1,493.3
Depreciation and amortization		62.9			8.8		0.4			72.1
Investment in joint venture		58.5			-		-			58.5
Purchases of property, plant and equipment ⁽¹⁾		59.5			8.8		-			68.3

For the year ended 2018	Mineral Fiber			Architectural Specialties		Unallocated Corporate			Total
Net sales to external customers	$	801.6		$	173.7	$	-		$	975.3
Equity (earnings) from joint venture		(74.9	)		-		-			(74.9	)
Segment operating income (loss)		223.8			34.3		(8.7	)		249.4
Segment assets		1,096.1			84.7		413.2			1,594.0
Depreciation and amortization		75.3			3.5		0.6			79.4
Investment in joint venture		40.8			-		-			40.8
Purchases of property, plant and equipment ⁽¹⁾		60.5			4.1		-			64.6

For the year ended 2017	Mineral Fiber			Architectural Specialties		Unallocated Corporate			Total
Net sales to external customers	$	756.4		$	137.2	$	-		$	893.6
Equity (earnings) from joint venture		(67.0	)		-		-			(67.0	)
Segment operating income (loss)		233.5			27.7		(17.4	)		243.8
Segment assets		1,193.5			53.2		320.7			1,567.4
Depreciation and amortization⁽¹⁾		59.2			1.8		6.0			67.0
Investment in joint venture		107.3			-		-			107.3
Purchases of property, plant and equipment ⁽¹⁾		76.1			1.6		-			77.7

Segment operating income (loss) is the measure of segment profit or loss reviewed by the chief operating decision maker. The sum of the segments’ operating income (loss) equals the total consolidated operating income as reported on our Consolidated Statements of Earnings and Comprehensive Income. The following reconciles our total consolidated operating income to earnings from continuing operations before income taxes. These items are only measured and managed on a consolidated basis:

Accounting policies of the segments are the same as those described in the summary of significant accounting policies.

The sales in the table below are allocated to geographic areas based on the location of our selling entities.

	2019		2018		2017
Geographic Areas
Net trade sales
Mineral Fiber:
United States and Latin America	$	769.0	$	739.2	$	699.8
Canada		57.6		62.4		56.6
Total Mineral Fiber		826.6		801.6		756.4

Architectural Specialties:
United States and Latin America		192.3		157.5		129.5
Canada		19.2		16.2		7.7
Total Architectural Specialties		211.5		173.7		137.2
Total net trade sales	$	1,038.1	$	975.3	$	893.6

	2019		2018
Property, plant and equipment, net at December 31,
Mineral Fiber:
United States	$	496.6	$	487.5
Total Mineral Fiber		496.6		487.5

Architectural Specialties:
United States	$	22.2	$	5.9
Canada		5.8		4.5
Total Architectural Specialties		28.0		10.4

Unallocated Corporate ⁽¹⁾		-		3.1
Total property, plant and equipment, net	$	524.6	$	501.0

Impairment testing of our tangible assets occurs whenever events or changes in circumstances indicate that the carrying amount of the asset group may not be recoverable.

In connection with the 2018 closing of our St. Helens, Oregon Mineral Fiber manufacturing facility we recorded $14.1 million in 2018 in cost of goods sold related to accelerated depreciation of property, plant and equipment. In 2017, we recorded $4.0 million in cost of goods sold related to accelerated depreciation of property, plant and equipment within our Mineral Fiber segment.

In September 2017, we made the decision to permanently close a previously idled plant in China. As a result, during 2017 we recorded $5.6 million in cost of goods sold for accelerated depreciation of machinery and equipment.