By the way, you can compute the effect of the popularity effect as well.
The dcity website tells that the popularity increases population like this :
bonus = ( popularity ^ 0.68 ) * 100 (in %)
So the total population would be : base_pop * ( 1 + ( popularity ^ 0.68 ) )

The exponant value was recently reduced : it used to be ( popularity ^ 0.7 ).
The change is not much but it had a big impact on my population, and left me with many empty job positions.