@anon84912554
I install Sky unit 9. december and then reset data 13. december when I set Sky on my roof.
In a period from 9. to 13.12 I have one sunny day, after that in december I don’t have any more sunny days.
In January I have nearly 9 sunny days. No full sunshine but mainly sunny in more of this days.
My Sky and further give bigger values then real.