Region
United States
179
Canada
19
Great Britain
15
European Union countries
14
Europe
11
Australia
5
Germany
5
Developing countries
4
Latin America
4
Africa
3
Brazil
3
Ireland
3
Israel
3
Japan
3
Mexico
3
Belgium
2
Colombia
2
Czech Republic
2
England
2
Ethiopia
2
Italy
2
Netherlands
2
Papua New Guinea
2
Soviet Union
2
Spain
2
Taiwan
2
Thailand
2
Washington (D.C.)
2
Algeria
1
Asia
1
California
1
Denmark
1
Europe Union countries
1
Europe, Eastern
1
European Economic Community countries
1
Former Soviet republics
1
Ghana
1
India
1
Middle East
1
New Zealand
1
Oceania
1
Scotland
1
Singapore
1
South Asia
1
Turkey
1
Virginia
1