The Excel LOGNORMDIST function calculates the Cumulative Log-Normal Distribution Function at a supplied value of x.
Syntax: LOGNORMDIST( x, mean, standard_dev )
Where the function arguments are:
|x||–||The value at which you want to evaluate the log-normal distribution function|
|mean||–||The arithmetic mean of ln(x)|
|standard_dev||–||The standard deviation of ln(x)|
Lognormdist Function Example
The chart on the right shows the the Log-Normal Cumulative Distribution Function for a variable, x. The mean of ln(x) is 10 and the standard deviation of ln(x) is 5.
If you want to calculate the value of this function at x = 12, this can be done using the Excel Lognormdist function, as follows:
=LOGNORMDIST( 12, 10, 5 )
This gives the result 0.066417115.
Lognormdist Function Errors
If you get an error from the Excel Lognormdist function this is likely to be one of the following:
|#NUM!||–||Occurs if the supplied x ≤ 0 or the supplied standard_dev ≤ 0|
|#VALUE!||–||Occurs if any of the supplied arguments are non-numeric|