Segments and Geographic Information

Until the acquisition of Cascade Microtech, we operated in one reportable segment relating to the design, development, manufacture and sale of high performance advanced probe cards. We currently operate in two reportable segments consisting of the Probe Cards Segment and the Systems Segment.

Our chief operating decision maker ("CODM") is our Chief Executive Officer, who reviews operating results to make decisions about allocating resources and assessing performance for the entire company.

The following table summarizes the operating results by reportable segment (dollars in thousands):



	Fiscal 2017
	Probe Cards			Systems			Corporate and Other			Total
Revenues	$	454,794		$	93,647		$	—		$	548,441
Gross profit	$	195,903		$	46,647		$	(26,953	)	$	215,597
Gross margin	43.1		%	49.8		%	—		%	39.3		%
Operating income (loss)	$	61,108		$	17,569		$	(32,376	)	$	46,301



	Fiscal 2016
	Probe Cards			Systems			Corporate and Other			Total
Revenues	$	337,970		$	45,911		$	—		$	383,881
Gross profit	$	121,407		$	23,925		$	(42,650	)	$	102,682
Gross margin	35.9		%	52.1		%	—		%	26.7		%
Operating income (loss)	$	49,382		$	8,968		$	(106,257	)	$	(47,907	)



	Fiscal 2015
	Probe Cards			Systems			Corporate and Other			Total
Revenues	$	282,358		$	—		$	—		$	282,358
Gross profit	$	99,199		$	—		$	(13,461	)	$	85,738
Gross margin	35.1		%	—		%	—		%	30.4		%
Operating income (loss)	$	39,964		$	—		$	(44,067	)	$	(4,103	)

Operating results provide useful information to our management for assessment of our performance and results of operations. Certain components of our operating results are utilized to determine executive compensation along with other measures.

Corporate and Other includes unallocated expenses relating to amortization of intangible assets, share-based compensation expense, acquisition-related costs, including charges related to inventory stepped up to fair value, and other costs, which are not used in evaluating the results of, or in allocating resources to, our reportable segments. Acquisition-related costs include transaction costs and any costs directly related to the acquisition and integration of acquired businesses.

The following table summarizes revenue, by geographic region, as a percentage of total revenues based upon ship-to location:



	Fiscal Year Ended
	December 30, 2017		December 31, 2016		December 26, 2015
United States	34.0	%	33.3	%	23.4	%
South Korea	14.9		17.1		25.2
Taiwan	17.7		14.9		21.9
Europe	8.2		12.9		9.0
Asia-Pacific⁽¹⁾	16.6		11.4		11.1
Japan	8.1		10.0		9.4
Rest of the world	0.5		0.4		—
Total Revenues	100.0	%	100.0	%	100.0	%

⁽¹⁾Asia-Pacific includes all countries in the region except Taiwan, Japan and South Korea, which are disclosed separately.

The following table summarizes revenue by product group (in thousands):



	Fiscal Year Ended
	December 30, 2017		December 31, 2016		December 26, 2015
Foundry & Logic	$	313,714	$	237,591	$	145,839
DRAM	124,685		86,910		125,512
Flash	16,395		13,469		11,007
Systems	93,647		45,911		—
Total revenues	$	548,441	$	383,881	$	282,358

Long-lived assets, comprised of Property, plant and equipment, net, Goodwill and Intangibles, net reported based on the location of the asset was as follows (in thousands):



	December 30, 2017		December 31, 2016		December 26, 2015
United States	$	299,574	$	323,369	$	77,257
Europe	30,922		30,903		655
Asia-Pacific⁽¹⁾	1,765		1,709		689
South Korea	487		733		1,128
Japan	825		510		295
Rest of the world	585		57		112
Total	$	334,158	$	357,281	$	80,136

⁽¹⁾ Asia-Pacific includes all countries in the region except Japan and South Korea, which are disclosed separately.