The following table presents combined information regarding the financial position of our unconsolidated affiliates accounted for using the equity method as of May 31:

(in thousands)	2018		2017
Cash	$	52,812	$	55,541
Other current assets		590,578		541,746
Current assets for discontinued operations		37,640		17,275
Noncurrent assets		358,927		342,938
Noncurrent assets for discontinued operations		-		18,168
Total assets	$	1,039,957	$	975,668
Current liabilities	$	166,493	$	148,056
Current liabilities for discontinued operations		7,142		8,891
Short-term borrowings		26,599		8,172
Current maturities of long-term debt		23,243		5,827
Long-term debt		259,588		268,711
Other noncurrent liabilities		17,536		20,890
Noncurrent liabilities for discontinued operations		-		490
Equity		539,356		514,631
Total liabilities and equity	$	1,039,957	$	975,668

The following table presents summarized financial information for our four largest unconsolidated affiliates as of, and for the fiscal years ended May 31. All other unconsolidated affiliates are combined and presented in the Other category, including WSP through March 1, 2016. On March 1, 2016, the Company obtained effective control over the operations of WSP and, as a result, began consolidating its financial results within those of Steel Processing.

(in thousands)	2018			2017			2016
Net sales
WAVE	$	360,395		$	334,031		$	329,050
ClarkDietrich		790,887			711,735			615,609
Serviacero Worthington		315,098			275,315			260,337
ArtiFlex		197,061			208,922			219,510
Other		28,578			17,784			74,214
Total net sales	$	1,692,019		$	1,547,787		$	1,498,720

Gross margin (loss)
WAVE	$	201,581		$	190,350		$	191,535
ClarkDietrich		97,437			128,098			95,427
Serviacero Worthington		32,396			37,080			15,328
ArtiFlex		18,266			22,829			30,181
Other		(6,399	)		(4,313	)		13,142
Total gross margin	$	343,281		$	374,044		$	345,613

Operating income (loss)
WAVE	$	158,697		$	158,030		$	162,026
ClarkDietrich		39,153			68,696			33,897
Serviacero Worthington		24,232			29,975			11,110
ArtiFlex		11,395			15,519			22,612
Other		(10,584	)		(8,407	)		6,910
Total operating income	$	222,893		$	263,813		$	236,555

Depreciation and amortization
WAVE	$	1,659		$	2,978		$	2,245
ClarkDietrich		11,864			12,718			14,289
Serviacero Worthington		3,919			3,862			3,508
ArtiFlex		5,515			5,850			6,105
Other		749			698			3,081
Total depreciation and amortization	$	23,706		$	26,106		$	29,228

Interest expense (income)
WAVE	$	8,365		$	7,182		$	6,635
ClarkDietrich		114			20			80
Serviacero Worthington		397			89			114
ArtiFlex		1,333			1,429			1,650
Other		(1	)		-			(10	)
Total interest expense	$	10,208		$	8,720		$	8,469

Income tax expense (benefit)
WAVE	$	119		$	2,398		$	(14	)
ClarkDietrich		-			-			-
Serviacero Worthington		5,141			11,740			6,249
ArtiFlex		208			(2	)		289
Other		-			(2	)		53
Total income tax expense	$	5,468		$	14,134		$	6,577

Net earnings (loss)
WAVE (1)	$	152,329		$	154,866		$	164,132
ClarkDietrich		39,138			69,122			58,539
Serviacero Worthington		17,577			18,140			6,246
ArtiFlex		9,854			14,092			20,673
Other		(11,922	)		(5,472	)		8,516
Total net earnings	$	206,976		$	250,748		$	258,106

(1)

On November 20, 2017, WAVE agreed to sell its business and operations in Europe and Asia to the Knauf Group, a family-owned manufacturer of building materials headquartered in Germany. WAVE has classified its businesses to be sold as discontinued operations. These net earnings include net income attributable to discontinued operations of $2,226,000, $6,775,000, and $8,930,000 in fiscal 2018, fiscal 2017, and fiscal 2016, respectively. All other amounts presented in the table above exclude the activity of the discontinued operations of WAVE