I had an idea.

Way back here I got, at least I think I got, possibly, this years only Standard distribution curve of Sunshine.

I noticed then we got usable light before 06:00 and, despite it being still quite light, we lost it @ about 21:00
SO
The idea is the occasional check on how much usable light as the year strolls by.  
Maybe not too often - you hope. (About Monthly?)
Today We had similar so it'll not be weekly, though it might be "Weakly".

Writing this "Tomorrow" (Sat)
It's now 21:00 - still broad daylight, ≈ 10/10 cloud - only 45W showing.
: ¬ ( 
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