57 visiting now: 35 USA 
8 Singapore 
6 Canada 
4 Brazil 
2 China 
2 Czech Republic 
2 UK 
2 Hong Kong 
1 Russia 
1 Saudi Arabia 
1 Germany 
1 Australia 
1 Ukraine 
1 Japan 
8 Singapore 6 Canada 4 Brazil 2 China 2 Czech Republic 2 UK 2 Hong Kong 1 Russia 1 Saudi Arabia 1 Germany 1 Australia 1 Ukraine 1 Japan