When clicking between groups in admin the user counts change.
You can see 160 change to 150 and 176 change to 174.
The actions taking place here are refreshing the page and clicking between groups.
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Is this a similar bug reported by @tobiaseigen here Group administration: inconsistent number of members shown if some members were removed ?
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I noted the mention of caching being a possible cause…
…however the members included in the group full_members_14_15 hasn’t been changed since April 2015.
They have also only been modified by the UI and not the API.
I think this is a dupe of my post. I can confirm it’s still happening on my sites.
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I just pushed a fix 
https://github.com/discourse/discourse/commit/79639e2dec11d2ae056e30b2bfd32ecfed6fec25
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Ready to be closed then? Great fix by the way
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