*Syntax: "NORMDIST " should read "LOGNORMDIST"
*Formulae: - I suspect that the integral may need to be from -infinity
not 0 for the cumulative dist function (as with NORMDIST). I can't find
this formula on the net - normally it seems to be quoted as
1/2+1/2*ERF((LN-u)/(s*SQRT(2))) - which does seem to produce the same
results, and may be preferable if it is standard practice. Or could be
defined in terms of NORMDIST or NORMSDIST which is the simplest.