Try the custom number format:

0,," ppm";-0,," ppm";@


--
Cordially,
Chip Pearson
Microsoft MVP - Excel
Pearson Software Consulting, LLC
www.cpearson.com
(email address is on the web site)


"hmm" wrote in message
...
I have numbers I would like expressed as parts per million (ppm). Just as
%
format displays the number multiplied by 100, ppm format should display
the
number multiplied by 1 million (and append the unit "ppm"). Is there a
way I
can enter this as a custom format, including in charts?