Table:
|  |  | Year Ended February 28, |  |
| --- | --- | --- | --- |
|  | 2019 | 2018 | 2017 |
| United States | 268,453 | 265,613 | 259,974 |
| Europe, Middle East and Africa | 49,496 | 45,830 | 49,918 |
| South America | 15,134 | 20,699 | 17,738 |
| Canada | 9,815 | 14,958 | 8,412 |
| Asia and Pacific Rim | 13,958 | 12,873 | 8,967 |
| All other | 6,944 | 5,939 | 6,093 |
|  | 363,800 | 365,912 | 351,102 |
Paragraphs:
Revenue by geographic area are as follows (in thousands):
Revenues by geographic area are based upon the country of billing. The geographic location of distributors and OEM customers may be different from the geographic location of the ultimate end users of the products and services provided by us. No single non-U.S. country accounted for more than 10% of our revenue in fiscal years ended February 28, 2019, 2018 and 2017.
Question:
What were revenues by geographic area based on?