I don't think the scale of Empires is anywhere near the same to make the two particularly comparable. Remember that Great Britain effectively bankrolled one side of the money incinerator that was the First Great War alone (at least for the first two years) which somewhat demonstrates the exceptional zenith of its power.

I've never been to Portugal, and don't know much about it.

Upon reading your comment, I casually looked up its economic stats and on first glance nothing jumped out at me.

So, what's wrong with Portugal?