Region
United States --
United States
20
Japan
4
Japan --
3
Singapore
3
Singapore --
3
Asia
2
Canada
2
China
2
China --
2
Developing countries
2
Developing countries --
2
Europe
2
Europe --
2
Korea (South)
2
Korea (South) --
2
Asia --
1
Canada --
1
Caribbean Area
1
Caribbean Area --
1
Central America
1
Central America --
1
Korea ()South) --
1
Malaysia
1
Malaysia --
1
Mexico
1
Mexico --
1
New Zealand
1
New Zealand --
1
Soviet Union
1
Soviet Union --
1