12. Geographical Information

The Company’s principal markets include America, Asia and Europe. The Company’s foreign operations are conducted primarily through its subsidiaries in China, Singapore, Israel, Taiwan, South Korea, United Kingdom and the Czech Republic. Sales by geographic area represent sales to unaffiliated customers and are based upon the location to which the products were shipped or performed. The following table sets forth revenue by geographic area (in thousands):

	Three Months Ended				Nine Months Ended
	September 28,		September 29,		September 28,		September 29,
	2018		2017		2018		2017
United States	$	123,655	$	138,866	$	467,616	$	372,571
China		11,803		6,834		30,782		24,947
Singapore		62,437		73,427		247,974		207,477
Austria		18,320		6,132		48,249		25,844
Other		17,864		17,351		44,513		44,626
	$	234,079	$	242,610	$	839,134	$	675,465

At September 28, 2018, approximately $78.7 million and $2.6 million of the Company’s net long-lived assets were located in Asia and Europe, respectively, and the remaining balances were located in the United States. At September 29, 2017, approximately $9.9 million and $1.6 million of the Company’s net long-lived assets were located in Asia and the Czech Republic, respectively, and the remaining balances were located in the United States.