The interesting thing here is that, on November 2018:
54,55% of the accounts created in 2009 were still active.
20,66% of the accounts created in 2010 were still active.
46,88% of the accounts created in 2011 were still active.
31,71% of the accounts created in 2012 were still active.
15,93% of the accounts created in 2013 were still active.
15,95% of the accounts created in 2014 were still active.
4,80% of the accounts created in 2015 were still active.
9,21% of the accounts created in 2016 were still active.
33,52% of the accounts created in 2017 were still active.
To take into consideration: existence of massive Newbie account creation on certain years (for bot spam I figure), forum hacks, etc. These facts affect wildly the percentages. The thread where the quote comes from details the information by Ranks.
The plot shows that there is likely periodic cycle (four-year period) like bitcoin price. Total new registered accounts (monthly) increased exponentially in 2013 and 2017, then plumetted later in 2014, and 2018. Drops in 2018 can be explained by merit system, Junior Member demotion, but I don't know that the forum had any type of new restrictive rules in 2014. Anyway, it is so interesting to know more than 33% of accounts created in 2017 were still active till Nov. 2018. I think if you make new statistics till July 2019, the percentage will decrease significantly.
Please read more here:
Assumed monthly statistics on registered accounts of bitcointalk.org (2009-2019)From what I knew about
History of bitcointalk.org's rank system, there are three rank systems
1. November 22, 2009 - January 22, 2018: Without activity requirements
2. June 18, 2013 - January 23, 2018: Activity requirements
3. January 24, 2018 - by now: Activity requirements + Merit requirements
