53 visiting now: 31 USA 
10 Canada 
8 Singapore 
2 China 
1 Taiwan 
1 Australia 
1 UK 
1 Russia 
10 Canada 8 Singapore 2 China 1 Taiwan 1 Australia 1 UK 1 Russia 10 Canada 8 Singapore 2 China 1 Taiwan 1 Australia 1 UK 1 Russia