Returns the inverse of the standard normal cumulative distribution. The distribution has a mean of zero and a standard deviation of one.
Syntax
NORMSINV(probability)
Probability is a probability corresponding to the normal distribution.
Remarks

If probability is nonnumeric, NORMSINV returns the #VALUE! error value.

If probability < 0 or if probability > 1, NORMSINV returns the #NUM! error value.
NORMSINV uses an iterative technique for calculating the function. Given a probability value, NORMSINV iterates until the result is accurate to within ± 3x10^7. If NORMSINV does not converge after 100 iterations, the function returns the #N/A error value.
Example
Formula 
Description ( Result) 
=NORMSINV(0.908789) 
Inverse of the standard normal cumulative distribution, with a probability of 0.908789 (1.3333) 