SQL*loader negative numbers

[Quoted] I posted this in cdo.servers, but no luck with responses yet so sorry if you've read this already.
I'm trying to load data using SQL*loader but can't find how to load signed numbers. The fields may or may not be signed eg 1234 or 1234-, so I can't put in a 'multiply by -1' . I've looked in the Utilities manual but can't work out how to describe the field in the control file (integer external? decimal external??) Any pointers would be greatly appreciated. TIA Sally Pearce
Financials DBA(for my sins) Received on Fri Feb 07 1997 - 00:00:00 CET