Numbers are deceiving. Though only 25 of the world's 193 countries have federal political systems, their citizens' make up 40 per cent of the world's population:

1. Argentina
2. Australia
3. Austria
4. Belgium
5. Bosnia and Herzegovina
6. Brazil
7. Canada
8. Comoros
9. Ethiopia
10. Germany
11. India
12. Malaysia
13. Mexico
14. Micronesia
15. Nigeria
16. Pakistan
17. Russia
18. St. Kitts and Nevis
19. Serbia and Montenegro
20. South Africa
21. Spain
22. Switzerland
23. United Arab Emirates
24. United States of America
25. Venezuela

Source: Handbook of Federal Countries: 2002, Montreal and Kingston: McGill-Queen's University Press, 2002.

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