Tech Report: Histograms per KPI

[alonkochba]

It's very useful to see histograms per KPI
A lot of very interesting data hides in the percentiles movement, for example green sites becoming much greener.

Simple single month (ignore label):

Monthly comparisons (advanced):

[tunetheweb]

Similar story to #1146. Looks potentially useful, but we don't have any visualisations like that at the moment (save for a plain old table). So make take a while to implement. Unless anyone else has time to work on this?

I would note that the histograms on the other reports on the site are a bit of a hidden feature and so very underused AFAIK.