The PPM bit can be appended by using

0" PPM"

as a custom format for the cell. However multiplying by a million is a
different matter it can be done but would be very confusing. For example if
you set up automatic multiplication by 1,000,000 then entering 3 would give a
result of 3m parts per million which I don't think is what you are aiming
for. Please post again if this isn't what you want.

"hmm" wrote:

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?