What is the average number of live viewers (online and TV) for top chess events like the world championship match and the candidates tournament? Are there some statistics publicly available?
It says (in Bulgarian): "The match Topalov - Anand (2010) made an absolute record on the Internet. For all 12 games together recorded 2 million links to the live broadcast of individual computers, but for just the last party - 300 000. Usually it is assumed that three people on average watched on a computer..."
For Anand - Carlsen 2014: https://www.chess.com/news/an-interview-with-ilya-merenzon-organizer-of-anand-carlsen-4530
"The total number of unique visitors was 10.5 million with the highest traffic on the last day of the match: 2 million visitors."
I make no warranty as to the validity of the accounting of these numbers.