 

             {                   }
             {       { elev+10 } }
             { 1.5 - { ------- } } * happystrollers_this_update
hap_yield =  {       { elev+20 } }
             {                   }
             --------------------------------------------------
                          (population + 1) / 5000



                 (old_hap * 48) + (hap_yield * etus)
new_hap_level =  -----------------------------------
                            (48 + etus)


              education_this_update
edu_yield =   ---------------------
                 population/4000


                 (old_edu * 196) + (edu_yield * etus)
new_edu_level =  ------------------------------------
                            (196 + etus)
            
