Tried to find resources that are reliable worldwide:
https://www.yes4cleanwater.org/files/CoutriesRejectedF.pdf
http://apps.who.int/iris/bitstream/handle/10665/43514/9241563192_eng.pdf;jsessionid=B50ED917B5A5C7EDCC857054AE1FB68B?sequence=1
Ontario, Alberta, and Manitoba have the highest rates of fluoridation, about 70–75%.
https://en.wikipedia.org/wiki/Fluoridation_by_country