>lnAmount = lnAmountDebit - lnAmountCredit
>wait windows "lnAmount = " + str(lnAmount, 20, 18)
>&& shows 0.000000000000455000

>Thanks again, at least there is a logical reason (not very smart from VFP) and I'm not crazy. ;-)

This computational "noise" is from the computer processor, and has been around since the oldest mainframe days, the result of binary calculation imprecision. Seen it in every language I've worked in...some day they will build in a fix, perhaps.