SEGMENT INFORMATION The Company determines its business segments and reports segment information in accordance with how the Companys chief operating decision maker (CODM) organizes the segments to evaluate performance, allocate resources and make business decisions. Segment results are based on the segments revenues and operating profit, where segment operating profit is defined as income from operations before unallocated costs. Expenses included in segment operating profit consist principally of direct selling and delivery costs as well as an allocation of certain shared services expenses. Certain corporate expenses are not allocated to specific segments as these expenses are not controllable at the segment level. Such expenses include certain types of professional fees, non-corporate taxes, compensation to non-employee directors and certain other general and administrative expenses, including compensation of specific groups of non-production employees. In addition, the Company does not allocate amortization of acquisition-related intangible assets, goodwill and other asset impairment charges, stock-based compensation expenses, acquisition-related costs and certain other one-time charges. These unallocated amounts are combined with total segment operating profit to arrive at consolidated income from operations as reported below in the reconciliation of segment operating profit to consolidated income before provision for/(benefit from) income taxes. Additionally, management has determined that it is not practical to allocate identifiable assets by segment since such assets are used interchangeably among the segments. The Company manages its business primarily based on the managerial responsibility for its client base and market. As managerial responsibility for a particular customer relationship generally correlates with the customers geographic location, there is a high degree of similarity between customer locations and the geographic boundaries of the Companys reportable segments. In some cases, managerial responsibility for a particular customer is assigned to a management team in another region and is usually based on the strength of the relationship between customer executives and particular members of EPAMs senior management team. In such cases, the customers activity would be reported through the management teams reportable segment. Revenues from external customers and operating profit, before unallocated expenses, by reportable segments for the three and nine months ended September 30, 2019 and 2018 , were as follows: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Segment revenues: North America $ 358,987 $ 280,838 $ 1,000,715 $ 769,137 Europe 205,123 171,482 596,798 516,320 Russia 24,164 16,208 63,945 53,374 Total segment revenues $ 588,274 $ 468,528 $ 1,661,458 $ 1,338,831 Segment operating profit: North America $ 79,310 $ 60,763 $ 213,114 $ 155,944 Europe 27,550 28,871 87,014 84,329 Russia 5,524 543 11,765 8,211 Total segment operating profit $ 112,384 $ 90,177 $ 311,893 $ 248,484 Intersegment transactions were excluded from the above on the basis that they are neither included in the measure of a segments profit and loss results, nor considered by the CODM during the review of segment results. There were no customers that accounted for more than 10% of total segment revenues during the three and nine months ended September 30, 2019 and 2018 . Accounts receivable and unbilled revenues are generally dispersed across the Companys customers in proportion to their revenues. There were no customers individually exceeding 10% of total accounts receivable and unbilled revenues as of September 30, 2019 and December 31, 2018 . Reconciliation of segment revenues to consolidated revenues and segment operating profit to consolidated income before provision for/(benefit from) income taxes is presented below: Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 Total segment revenues $ 588,274 $ 468,528 $ 1,661,458 $ 1,338,831 Other income included in segment revenues (171 ) (342 ) (435 ) (850 ) Revenues $ 588,103 $ 468,186 $ 1,661,023 $ 1,337,981 Total segment operating profit: $ 112,384 $ 90,177 $ 311,893 $ 248,484 Unallocated amounts: Other income included in segment revenues (171 ) (342 ) (435 ) (850 ) Stock-based compensation expense (15,471 ) (15,330 ) (53,024 ) (46,736 ) Non-corporate taxes (3,960 ) (2,063 ) (8,126 ) (7,041 ) Professional fees (1,502 ) (1,420 ) (3,826 ) (4,736 ) Depreciation and amortization expense (2,585 ) (2,011 ) (7,328 ) (5,754 ) Bank charges (645 ) (782 ) (1,937 ) (1,950 ) One-time charges and other acquisition-related expenses (1,142 ) (155 ) (2,503 ) (2,016 ) Other operating expenses (6,343 ) (3,514 ) (16,609 ) (11,907 ) Income from operations 80,565 64,560 218,105 167,494 Interest and other income, net 2,509 1,941 6,775 2,442 Foreign exchange (loss)/gain (3,105 ) (514 ) (10,151 ) 1,069 Income before provision for/(benefit from) income taxes $ 79,969 $ 65,987 $ 214,729 $ 171,005 Geographic Area Information Long-lived assets include property and equipment, net of accumulated depreciation and amortization, and management has determined that it is not practical to allocate these assets by segment since such assets are used interchangeably among the segments. Physical locations and values of the Companys long-lived assets are presented below: As of September 30, 2019 As of December 31, 2018 Belarus $ 48,521 $ 50,085 Ukraine 16,077 8,433 United States 13,934 13,101 Russia 12,514 9,902 India 6,742 7,019 Hungary 3,329 3,168 China 3,132 2,651 Poland 2,900 2,637 Other 8,172 5,650 Total $ 115,321 $ 102,646 The table below presents information about the Companys revenues by customer location for the three and nine months ended September 30, 2019 and 2018 : Three Months Ended September 30, Nine Months Ended September 30, 2019 2018 2019 2018 United States $ 340,803 $ 266,065 $ 959,471 $ 736,579 United Kingdom 74,992 50,482 209,773 152,315 Switzerland 38,781 35,524 110,378 105,396 Russia 23,668 15,609 62,020 51,930 Netherlands 22,161 17,031 63,816 51,934 Germany 20,940 20,732 59,716 60,331 Canada 17,582 18,008 50,339 51,391 Other 49,176 44,735 145,510 128,105 Total $ 588,103 $ 468,186 $ 1,661,023 $ 1,337,981