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I started doing this a few years ago and complemented the data over the years, at some point I added Kazakhstan and Azerbaijan. I always look if there are new countries I should include but for the coefficient points from 13/14 - 22/23 as well as 15/16-24/25 these countries represent exactly the Top-32.
I did this because I found that the 5-year scores were subject to very unsustainable fluctuations and this gives a better overview about the "real" trends. For example Turkey crashed down to 20th place in the 5-year-ranking lately but this graph shows that the reports of Turkey's demise have been greatly exaggerated. These were just usual fluctuations that you always have over such a short period of 5 seasons, they bounced back very fast and in "my" graph which is more robust to fluctuations they didn't drop a single rank during that time.
Unlike Turkey though, the downfalls of Romania and Belarus are for real. Starting the count from 20/21 Belarus is 3rd to last in front of San Marino and just slightly getting the edge over Gibraltar, that was shocking to me, I remember times when BATE Borisov played in the Champions League and 7 years ago I harshly got to witness Dinamo Minsk knocking out Salzburg from the Europa League qualification. But as said before when counting back until 15/16 they still keep the 32nd spot so let's not overreact (yet).
By taking out 13/14 and 14/15, the inevitable finally happened: England overtook Spain, France as 5th and Portugal as 6th are still going rock solid.
The countries in the legend are sorted by the ranking at the starting point.
(and sorry to the colorblind people I concede this graph will be unreadable to you)