As a sort of "see also", I'd like to add that I have recently created some queries to investigate the cumulative distribution of time-to-close or time-to-deletion:
Update: Replaced a
min with a
max in the SQL (because
ntile counts from 1, and I want to use 50 as marking the median). Updated results accordingly.
E.g. about 5% of the closed questions found in SEDE got closed within 20 minutes. Median time-to-close is about 6.7h however. When considering deletions as well, about 10% got closed/deleted within 20 minutes, Median time being 10.1h.
Caveat: My SQL is rusty, and it is easy to misinterpret data.
When experimenting with SEDE, I often end up with lots of variants of one query.
Better craft your own variants according to your curiosity.