My theory is that the colder it is, the more kids tend to play inside =)

According to the TopCoder algorithm competition stats:

1 Russian Federation 2930.06
2 China 2843.33
3 Poland 2842.79
4 Ukraine 2557.06
5 Japan 2483.83
6 Canada 2426.56
7 United States 2320.98
8 Slovakia 2291.73
9 South Korea 2226.98
10 Belarus 2206.81

Let's just hope the next war isn't fought with robots.