algorithm behind the Lift Chart

Does anyone know the algorithm behind the Lift Chart? If yes, can you
please point me to the right direction? I could not find anything on the
web...



Assuming x is profit and y is the probability, the algorithm behind the
Profit Chart seems to be this:



1) Calculate profit for each percent point: (hits*Revenue per
individual) - (hits + misses)*[individual cost]

2) Calculate cumulative profit from 0 percent to the current percent
point - [Fixed cost]



I am really not very sure how the "Population" is used within Profit Chart.



Regards,

Igor