25 visiting now: 10 China 
6 USA 
3 Singapore 
2 Russia 
1 Saudi Arabia 
1 Colombia 
1 Iran 
1 Vietnam 
6 USA 3 Singapore 2 Russia 1 Saudi Arabia 1 Colombia 1 Iran 1 Vietnam 6 USA 3 Singapore 2 Russia 1 Saudi Arabia 1 Colombia 1 Iran 1 Vietnam