I believe you'll find 333 functions available in Excel 2003. That can be
obtained or verified through Excel 2003's Help feature.
As to how many of those an individual 'average' Excel user has knowledge of
or makes regular use of, well I don't have any stats on that at all.
But the question is 'what is an average user'? The functions are divided
into 11 major groups, and I can envision particular niche users being
familiar with perhaps a basic core group or two (math and text) with a
smattering from other areas, and yet no knowledge of anything in other areas
at all. For example: if someone asked me about the proper use of the BESSELI
or BESSELY functions, I'd be totally clueless. Those are in the Engineering
group. But then so are Bin2Hex and Bin2Dec which I am familiar with.
A rough guess, based on nothing other than gut feeling, is that any given
'average' Excel user who actually has figured out there are functions that
can be used is somewhere in the neighborhood of 5 to 10%, or roughly 15 to 35
functions that they use. I may be overly generous in my estimation.
