Hi Lbass, the refined spec which i now have is:
the columns are the months which are based on date diffs as so Month2:
if Datediff("m",{@Placement Month Start},{debt_trans.tx-date}) <= 1 and
{debt_trans.tran-code} startswith ["DR1","DR3","DR4","DR5","DR309"] then {debt_trans.tx-amount}
@Placement Month Start:
Date(Year({debt.dt-datinstr}),Month({debt.dt-datinstr}),1)
month 1 would be dates from 1/1 to 14/2 the diff2 would be 15/2 to 14/3 and 15/3 to 14/4
thanks for your help