Hi!
I’ve been working with your data for the Netherlands and I noticed that the average CF values mentioned in the main graph are slightly different than the ones I calculated.
E.g. in the main graph I see a value of 11.74% in 1985 for PV (Merra-2), yet when I calculate an average over all the hours I get a slightly different value (11,686%).
For the values in the graph, did you e.g. first calculate the daily average and then used that for an annual average? Not sure which calculation would make more sense… so if you have arguments why you did it the way you did, that would be greatly appreciated as well! 
Thanks in advance for your input!
Iris