BUG: masked mean unnecessarily overflowing
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Do we want to add mean to the Masked Array interface (I would say yes, but want to check anyway)? This would simplify things a bit.

cc @jorisvandenbossche 
Ah, nice, this is possible now because we require numpy >= 1.20 (the `where` keyword was only added later to `mean`)

> Do we want to add mean to the Masked Array interface (I would say yes, but want to check anyway)? This would simplify things a bit.

Yeah, I am not really sure why historically sum, prod, etc are methods, while mean is only handled inside `_reduce` Yes, numpy now supports this in every version we need.

Ok great, confused me a little bit too Added as method