Cities losing population

[Pomphis]

I believe I read about this before, but I don´t remember where.

I have several cities which used to have 25+ populations. I built Metropolitan Administrations. None became unhappy or unhealthy. But suddenly I notice that populations have been reduced to numbers between 16 and 23. I also notice that quite a few of them have zero stored food, that is their populations are now stagnant. The Metropolitan Administrations are still there. All affected cities are old in my core territory. I have quite a few Agents between other civs and my core territory and also one Agent in each city and did not catch any spies, I also got no Messages about enemies sabotaging anything.

 

[45°38'N-13°47'E]

I believe I read about this before, but I don´t remember where.

I have several cities which used to have 25+ populations. I built Metropolitan Administrations. None became unhappy or unhealthy. But suddenly I notice that populations have been reduced to numbers between 16 and 23. I also notice that quite a few of them have zero stored food, that is their populations are now stagnant. The Metropolitan Administrations are still there. All affected cities are old in my core territory. I have quite a few Agents between other civs and my core territory and also one Agent in each city and did not catch any spies, I also got no Messages about enemies sabotaging anything.

Check how much food every tile is producing. It might have been temporarily reducted by a meteor or volcano event.