How is that instructive? The British empire was mostly gone by the 1950s and a hell of a lot happened after that. It would be more instructive to look at Britain just before WW1 compared to the other countries.

At their peak, virtually all of the aforementioned empires brought enormous wealth to the homeland. It might not be profitable in the long run, but the long run can mean centuries before it becomes a net negative.

Also, Norway, Sweden, and Denmark were part of a Danish empire at one point.