I don't understand the calculation of food in cities. Is there any CivFanatic here who would help me sort it out? I thought the amount of food was just a simple sum of food on worked squares and the concepts of corruption or waste were not included in Civ5. But it seems there is something like this, because some food is missing in my cities. Please take a look at attached screenshot. Why are there just 5 foods from the terrain when working one 4-food tile and 2 foods are at the tile of the city itself? (I have unemployed all other citizens so that it is more clearly visible.) Strange thing is that when I use another 4-food tile (fishes), it's OK and there are 6 foods available. Am I missing some important game concept? I have found nothing in Civilopedia and also Google didn't help much. Thank you for an explanation.