Continent | Country | Volume 1 1960 | Volume 4 1975 | Volume 6 1985 | Volume 8 1995 | Volume 9 2000 |
---|---|---|---|---|---|---|
North America | USA (New York State) | 0.5 | 1.1 | 0.8 | 1.0 | 1.1 |
 | USA (California) | Na | 0.6 | 0.5 | 0.6 | 0.7 |
 | Canada (Alberta) | 0.4 | 0.7 | 0.6 | 0.6 | 0.5 |
 | Canada (Ontario) | Na | Na | 0.6 | 0.6 | 0.7 |
South/Central America | Columbia | 0.3 | 0.5 | 0.4 | 0.1 | 0.3 |
 | Cuba | Na | 0.1 | 0.2 | 0.3 | Na |
 | Brazil (Goiania) | Na | Na | 0.4 | 0.7 | 0.8 |
Europe | UK (South Thames) | 0.5 | 0.4 | 0.5 | 0.5 | 0.6 |
 | Denmark | 0.4 | 0.4 | 0.5 | 0.5 | 0.6 |
 | Sweden | 0.4 | 0.5 | 0.4 | 0.4 | 0.4 |
 | Norway | 0.3 | 0.3 | 0.5 | 0.4 | 0.4 |
Asia | Israel (Jews) | 1.4 | 1.1 | 0.8 | 1.4 | 1.1 |
 | Japan (Osaka) | Na | 0.1 | 0.2 | 0.2 | 0.2 |
 | India (Mumbai) | Na | 0.3 | 0.4 | 0.3 | 0.4 |
 | China (Shanghai) | Na | 0.5 | 0.3 | 0.3 | 0.4 |
Africa | Uganda | 0.3 | Na | Na | 0.1 | 1.4 |
 | Algeria | Na | Na | 0.8 | 0.7 | 0.6 |
 | Mali | Na | Na | 0.8 | 0.8 | Na |
Australia | New South Wales | Na | 0.7 | 0.7 | 0.6 | 0.7 |