Today (March 19, 2020) first time count of registrations per round became greater than fantastic 18000. To be presice it was 18180 (just one more and it would be palindrome). But only one (!) year ago it became more than 10000, so, it increased almost twice. Yes, we are sick of sports programming and it's contagious.
Less words, more pictures:
Three notable things:
- March, 2014: Black day. I've already forgot about it. Now with even with more than 10k participants codeforces has almost no queue in the beginning of contests;
- September, 2015: The Second Revolution of Colors and Titles;
- Upper envelope of this graph is combined contest, such as Hello/Goodbye/Global rounds.