28 visiting now: 11 China 
6 USA 
3 Russia 
2 Belgium 
1 Iraq 
1 Chile 
1 Iran 
1 Egypt 
1 Singapore 
1 Brazil 
6 USA 3 Russia 2 Belgium 1 Iraq 1 Chile 1 Iran 1 Egypt 1 Singapore 1 Brazil 6 USA 3 Russia 2 Belgium 1 Iraq 1 Chile 1 Iran 1 Egypt 1 Singapore 1 Brazil