72 visiting now: 34 USA 
10 Singapore 
10 Belgium 
6 Czech Republic 
4 Canada 
3 France 
2 Germany 
2 India 
1 Poland 
1 South Africa 
1 Taiwan 
1 UK 
1 Netherlands 
1 China 
10 Singapore 10 Belgium 6 Czech Republic 4 Canada 3 France 2 Germany 2 India 1 Poland 1 South Africa 1 Taiwan 1 UK 1 Netherlands 1 China