Business Segments, Customer Concentrations and Geographic Information

We operate as a single operating segment as managed by our Chief Executive Officer, who is considered our chief operating decision maker ("CODM"). The CODM bears the ultimate responsibility for, and is actively engaged in, the allocation of resources and the evaluation of our operating and financial results. We have concluded that we have a single operating segment based on the following:


•	We are managed under a functionally-based organizational structure with the head of each function reporting directly to the CODM;


•	We assess performance, including incentive compensation, based on consolidated operating performance and financial results;


•	Our CODM allocates resources and makes other operating decisions based on specific customer business opportunities and


•	We have an integrated process for the design, development and manufacturing services we provide to all of our customers. We also have centralized sales and administrative functions.

Net sales by product group consist of the following:



	For the Year Ended December 31,
	2018		2017		2016
	(In thousands)
Advanced Products	$	2,118,571	$	1,966,483	$	1,703,052
Mainstream Products	2,197,895		2,240,548		2,224,797
Total net sales	$	4,316,466	$	4,207,031	$	3,927,849


(1)	Advanced products include flip chip and wafer-level processing and related test services.


(2)	Mainstream products include wirebond packaging and related test services.

Net sales by end market consist of the following:



	For the Year Ended December 31,
	2018		2017		2016
Communications (smartphones, tablets, handheld devices)	44	%	43	%	42	%
Automotive, industrial and other (driver assist, infotainment, safety, performance)	26	%	26	%	26	%
Computing (datacenter, infrastructure, PC/laptop, storage)	18	%	18	%	18	%
Consumer (set-top boxes, televisions, connected home, personal electronics, visual imaging)	12	%	13	%	14	%
Total net sales	100	%	100	%	100	%

Net sales by region based on customer headquarters location consist of the following:



	For the Year Ended December 31,
	2018		2017		2016
	(In thousands)
Japan	$	1,156,797	$	1,210,296	$	1,162,729
Europe, Middle East and Africa	605,932		540,126		490,738
Asia Pacific (excluding Japan)	535,894		837,014		630,837
Total foreign countries	2,298,623		2,587,436		2,284,304
United States	2,017,843		1,619,595		1,643,545
Total net sales	$	4,316,466	$	4,207,031	$	3,927,849

One customer accounted for 10.2%, 14.3%, and 15.7% of net sales in 2018, 2017 and 2016, respectively. A second customer accounted for 12.9% of net sales in 2016.

Property, plant and equipment, net, based on physical location, consist of the following:



	December 31,
	2018		2017
	(In thousands)
China	$	472,858	$	528,739
Japan	219,373		246,223
Korea	1,213,838		1,131,271
Malaysia	47,491		47,922
Philippines	270,562		309,425
Portugal	63,323		64,578
Taiwan	352,576		356,174
Other foreign countries	170		216
Total foreign countries	2,640,191		2,684,548
United States	10,257		10,517
Total property, plant and equipment, net	$	2,650,448	$	2,695,065