# NORMINV function

Returns the inverse of the normal cumulative distribution for the specified mean and standard deviation.

Syntax

NORMINV(probability,mean,standard_dev)

Probability     is a probability corresponding to the normal distribution.

Mean     is the arithmetic mean of the distribution.

Standard_dev     is the standard deviation of the distribution.

Remarks

• If any argument is nonnumeric, NORMINV returns the #VALUE! error value.
• If probability < 0 or if probability > 1, NORMINV returns the #NUM! error value.
• If standard_dev ≤ 0, NORMINV returns the #NUM! error value.
• If mean = 0 and standard_dev = 1, NORMINV uses the standard normal distribution (see NORMSINV).

Given a value for probability, NORMINV seeks that value x such that NORMDIST(x, mean, standard_dev, TRUE) = probability. Thus, precision of NORMINV depends on precision of NORMDIST. NORMINV uses an iterative search technique. If the search has not converged after 100 iterations, the function returns the #N/A error value.

Example

The example may be easier to understand if you copy it to a blank worksheet.

• Create a blank workbook or worksheet.
• Select the example in the Help topic.

Note   Do not select the row or column headers.

Selecting an example from Help
• Press CTRL+C.
• In the worksheet, select cell A1, and press CTRL+V.
• To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Formulas tab, in the Formula Auditing group, click the Show Formulas button.
A B
Data Description
0.908789 Probability corresponding to the normal distribution
40 Arithmetic mean of the distribution
1.5 Standard deviation of the distribution
Formula Description (Result)
=NORMINV(A2,A3,A4) Inverse of the normal cumulative distribution for the terms above (42)

Applies to:
Excel 2007