32 visiting now: 15 USA 
8 China 
2 Germany 
2 India 
1 Slovakia 
1 UK 
1 Brazil 
1 Russia 
1 South Africa 
8 China 2 Germany 2 India 1 Slovakia 1 UK 1 Brazil 1 Russia 1 South Africa 8 China 2 Germany 2 India 1 Slovakia 1 UK 1 Brazil 1 Russia 1 South Africa