Happiness reflects the mental condition of a city's citizens. Nearly everything affects this condition, but <l:6,87>wages<e>, <l:6,89>rations<e>, and <l:6,88>workday<e> have the greatest effects. When a <l:6,104>city<e> is unhappy, it bears the threat of <l:6,120>rioting<e> or <l:6,121>revolting<e>. When a city is very happy, it will celebrate, growing twice as quickly.