Application After Enhancement Project

AFP = [(UFPB + ADD + CHGA) - (CHGB + DEL)] * VAFA

Where:

UFPB = Unadjusted Function Point Count Before Enhancement.
AFP = Application Function Point Count
DEL = is the number of function points deleted (the negative value).
All other acronyms are the same as before.

Of course, an enhancement calculation can add and/or Delete functionality from the UFPB. Added functionality can be due to new components or added functionality can be due to increase in size of existing components. For example, an existing external input could go from a low to an average – valued at 3 to 4.

In Practice

Normally VAFA = VAFB = VAF, so the equation can be re-arranged

AFP = (UFPB+ADD + CHGA-CHGB – DEL)* VAF

Lets assume that CHGA = CHGB and DEL = 0.

Then AFP= (UFPB + ADD) * VAFA