Hi Wallaby,

Arno your formula give me an error message "value" once typed in. I
assume that it must be the formatting. when I type in a number 15- it
converts, but with the number as 21.561,00- no luck.

try
=IF(right(a1,1)="-", left(value(a1), len(a1)-1)*(-1), a1)

if this does not work post some sample data of the as400 and tell me
what the result of
=left(a1, len(a1)-1)
exactly is. (It should be a number, if it is a text you'll get #value.)
Maybe we have to trim or use some other text-functions to make it work.

arno