Any region can make a profit in an investment, with careful management. The type of region isn't that important.
Remember a few key factors:
- The higher the gold rating, the more expensive the investment. A rural may only cost 100 gold for an investment, while larger cities may require 400, 500, or even more gold.
- The higher the gold rating, the less of a percentage boost you get to production. A rural may get boosted to 220% or more, but a city will generally go to about 160%, or maybe less.
- The higher above the normal, sustainable value the production goes, the faster it falls off.
- If production does not go above the normal sustainable value, it will not fall. This can be used to rapidly recover a region from looting.
- Food production cannot go over 100%, regardless of how high production goes.
- Gold production can go over 100%.
And most importantly:
It seems I was misread. I never said they never produce profits. I used to usually get profits. I was just stating I was not getting any lately, out of the last 5 or so.
You invest wherever you want. If your goal is to boost production over 100%, cities are your best bet I'd say. If you just want to bring it to 100%, then depends on you.
I've invested in rurals and townslands with suboptimal production levels in order to increase their food output, to make sure I had a steady supply from them, while helping them out a little extra. I wouldn't have done it if their production was at 100%, though.
Speaking of which... WHY won't food production go over 100%?