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11:17 AM
Now there are 828 questions with deprecated tags. You can compare this with numbers from August 25, June 2, May 1, March 3, etc.
It seems that the number has been around 830 for some time.
with 297 questions, 168 if we omit the most frequent algebra-related top-level tags and 90 questions with no top-level tags.
with 375 questions, 225 if we omit frequent geometry-related top-level tags and 127 with no top-level tags at all.
contains 157 questions, 74 if we omit co.combinatorics, 37 with no top-level tag at all.
Also deprecating of (convexity) was discussed on meta. It was also suggested to deprecate (continuity).
There are 197 questions where was removed, 755 questions where was removed 91 questions where was removed.
You can find queries returning those posts here: chat.stackexchange.com/transcript/message/49179918#49179918 You can even check which users have edited them away: chat.stackexchange.com/transcript/10243/2019/4/28 and below
Some time ago I have posted also short analysis checking how many users contributed to the removal of the deprecated tags: chat.stackexchange.com/transcript/10243/2019/6/15
As I have mentioned before, it would be not difficult to prevent deprecated tags at least from being added to new questions: The existing deprecated tags should be blacklisted and Blacklisting (deprecated) tag while they still exist.
There are 109056 questions on the site, 85007 questions with a top-level tag, 90212 questions if we also count (linear-algebra), (graph-theory) and (set-theory).
22.052% of questions without top-level tags, 17.279% of questions if we take the less strict interpretation.
Here are the links used to find the posts with top-level tags: chat.stackexchange.com/transcript/10243/2018/10/27
 

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