Had some free time so I went to Wiki to put this together. For the Heavyweights and Cruiserweights I used their weight for their last fight. For Mayweather I used 150 pounds since he holds belts at 147 and 154, for everyone else I use the max weight for each class (ex: 175 for Kovalev) . I show the heaviest champion and lowest, plus the average of all of them.
United States 18 (High:219, Low: 118, AVG: 148.6)
Mexico 8 (High:130, Low:108, AVG: 117.5)
Japan 8 (High:130, Low:105, AVG: 117.3)
Russia 5 (High:198, Low:126, AVG: 173)
UK 5 (High:160, Low: 118, AVG: 133.8)
Cuba 4 (High:199, Low:122, AVG: 152.5)
Germany 3 (High:200, Low:168, AVG: 181)
Philippines 3 (High:147, Low: 108, AVG:121)
Thailand 3 (High:112, Low:105, AVG:109)
Ukraine 2 (High:245, Low:126, AVG:185.5)
Colombia 2 (High:135, Low:122, AVG:128.5)
Venezuela 2 (High:135, Low:118, AVG:126.5)
Argentina 2 (High:126, Low:112, AVG: 119)
South Africa 2 (High:115, Low:105, AVG:110)
Only 1 Champion
Uzbekistan 246
France 200
Canada 175
Kazakhstan 160
Puerto Rico 160
Ireland 160
Jamaica 126
Peru 126
Dominican Republic 118
Nicaragua 112
United States 18 (High:219, Low: 118, AVG: 148.6)
Mexico 8 (High:130, Low:108, AVG: 117.5)
Japan 8 (High:130, Low:105, AVG: 117.3)
Russia 5 (High:198, Low:126, AVG: 173)
UK 5 (High:160, Low: 118, AVG: 133.8)
Cuba 4 (High:199, Low:122, AVG: 152.5)
Germany 3 (High:200, Low:168, AVG: 181)
Philippines 3 (High:147, Low: 108, AVG:121)
Thailand 3 (High:112, Low:105, AVG:109)
Ukraine 2 (High:245, Low:126, AVG:185.5)
Colombia 2 (High:135, Low:122, AVG:128.5)
Venezuela 2 (High:135, Low:118, AVG:126.5)
Argentina 2 (High:126, Low:112, AVG: 119)
South Africa 2 (High:115, Low:105, AVG:110)
Only 1 Champion
Uzbekistan 246
France 200
Canada 175
Kazakhstan 160
Puerto Rico 160
Ireland 160
Jamaica 126
Peru 126
Dominican Republic 118
Nicaragua 112
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