Rank	Countries/Territories	Count	Percent
1	United States	143	29.4%
2	China	137	28.2%
3	Germany	89	18.3%
4	Italy	20	4.1%
5	Netherlands	17	3.5%
6	Japan	12	2.5%
7	Canada	10	2.1%
8	Korea, Republic of	8	1.6%
9	Australia	6	1.2%
10	Switzerland	6	1.2%
11	France	5	1%
12	Mongolia	4	0.8%
13	Cyprus	4	0.8%
14	Taiwan	4	0.8%
15	Russia	3	0.6%
16	Singapore	3	0.6%
17	United Kingdom	3	0.6%
18	Argentina	3	0.6%
19	Iran, Islamic Republic of	3	0.6%
20	Peru	2	0.4%
21	Brazil	2	0.4%
22	Hong Kong	1	0.2%
23	Ukraine	1	0.2%