you don't have to calculate these values yourself. FullProf has an option, which creates a output file for geometric calculations (GC) and bond valence sum (BVS) etc. You can also get a reflections file with a list of reflections, hkl indices, FWHM, I_cal, I_obs etc.
If you use the PCR editor, you'll have to check the corresponding boxes in the "output information" tab (and define the maximum interatomic distance for GC). Alternatively, you can add the corresponding commands manually to your pcr-file.