Percentage of Optimal Cities
Determines what percentage of the optimal number of cities setting (found on the world sizes page) is actually optimal on the selected difficulty level. If this value is 100%, the optimal number of cities will be equal to the default setting for the given world size. At 50%, the optimal number of cities is halved. At 200%, the optimal number of cities is doubled. This value will not match the value on the World Sizes page exactly because the corruption setting of the player's government type is also a modifier.