It's a list made of 50 songs most successful in televoting (audience or public vote) according to a percentage of available points. Every song's amount of televoting points was divided by maximum possible score which the song could be awarded by televoting.
The video includes songs which competed in the finals from 1998 to 2021 excluding 2002 and 2013. If the rules of the contest make juries an exception due to an invalidity of the televoting, then these jury points are accounted. In 2001, when 100% jury and 50/50 voting systems were optional, most countries went for 100% televoting. That's why this year was included. In 2002, a lot more countries adopted the 50/50 system and the split results weren't released. In 2013, split average rankings were published instead of split points, so televoting points are not available.
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