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, aesthetic appeal and health attributes. 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, and a portion of our Architectural Specialties revenues are 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 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 consists 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 2020	Mineral Fiber			Architectural Specialties		Unallocated Corporate			Total
Net sales to external customers	$	726.0		$	210.9	$	-		$	936.9
Equity (earnings) from joint venture		(64.0	)		-		-			(64.0	)
Segment operating income		218.7			22.3		13.8			254.8
Segment assets		1,101.1			357.7		259.7			1,718.5
Depreciation and amortization		71.8			12.2		-			84.0
Investment in joint venture		41.2			-		-			41.2
Purchases of property, plant and equipment		45.5			9.9		-			55.4

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

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 Operations and Comprehensive Income. The following reconciles our total consolidated operating income to (loss) 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.

	2020		2019		2018
Geographic Areas
Net sales
Mineral Fiber:
United States	$	674.1	$	769.0	$	739.2
Canada		51.9		57.6		62.4
Total Mineral Fiber		726.0		826.6		801.6

Architectural Specialties:
United States	$	192.8	$	192.3	$	157.5
Canada		18.1		19.2		16.2
Total Architectural Specialties		210.9		211.5		173.7
Total net sales	$	936.9	$	1,038.1	$	975.3

	2020		2019
Property, plant and equipment, net at December 31,
Mineral Fiber:
United States	$	486.0	$	496.6
Total Mineral Fiber		486.0		496.6

Architectural Specialties:
United States	$	38.2	$	22.2
Canada		5.7		5.8
Total Architectural Specialties		43.9		28.0
Total property, plant and equipment, net	$	529.9	$	524.6

During 2020, we recorded a $21.0 million gain related to the sale of our idled mineral fiber plant in China, inclusive of accumulated foreign currency translation gains.

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.