You want to mod this one:

Code:
  <factor name="SOF_SQUALOUR">
         <pip_modifier value="0.25"/>
         <castle_modifier value="0.25"/>
         <pip_min value="0"/>
         <pip_max value="16"/>
      </factor>
SPF determines how many a factor modifies population
SOF determines how many a factor modifies public order
SIF determines how many a factor modifies income