hi, trying to be able to modify a formula, to pick the number of columns
desired for a calculation. examples below are for 3 columns, would range
from 2-10 columns.

=IF(K9=0,"",((ED9/EE9%)+(EE9/EF9%)+(EF9/EG9%))-300)

is a percent change formula: fm/to%-100
got some help with:

=IF(K9=0,"",SUMPRODUCT(ED9:EF9/EE9:EG9%-100))

would I use INDIRECT, MOD.. think would prefer a multplication? for
external entry in one fixed cell, e.g.: 3 (as above). thanks