How are villagers "produced"?

[Krum]

The population grows by itself. You can help its growth by researching medicine and building Granaries. The formula of population growth per hour is as follows:

(30+1 for every 1000+granaries)*the bonus of the province*the medicine level

For example if you have 10 000 villagers in a province with plains, and you have 5th level granaries and 2nd level medicine, the growth will be as follows: (30+10+5)*1.2*1.1=59,4 = 59 villagers per hour.