How many pools are there in the world?

We asked for it very often, so we did some research through the industry associations and we also asked Fluidra, the Spanish multinational, leader of the swimming pools and wellness market in Europe. Thanks to their answers, we managed to compose a puzzle but unfortunately many pieces are still missing. For example, nobody has been able to tell us how many private pools are in China, South Africa, Canada or Mexico (or in many other countries in the world). So our global search continues. Indeed, if someone has useful information, share it with us writing to info@fingerpools.com .
Here are the data collected so far:

Italy: 365.000
France: 1,700,000
UK: 280,000
Germany: 900,000
Spain: 1,100,000
Portugal: 110,000
Austria: 100,000
Switzerland: 90,000
Turkey: 150,000
Russia: 15,000
Bulgaria: 10,000
Scandinavia: 92,000
Balkans: 15,000
Baltic: 15,000
Greece: 70,000
Ireland: 15,000
Poland: 15,000
Czech Republic: 100,000
Slovakia: 30,000
Romania: 20,000
Hungary: 70,000
Benelux: 90,000
Australia: 1,000,000
United States: 5,400,000

Estimated existing swimming pools in the world: 22,000,000.