# NORMINV

The NORMINV function calculates the inverse of the normal cumulative distribution for a specified probability. It is commonly used in statistics and finance to find the value for a given probability in a standard normal distribution.

## Syntax

=NORMINV(`Probability`, `Mean`, `Standard deviation`)

Imagine you're exploring the realm of statistics or finance, seeking to decipher the value associated with a particular probability in a standard normal distribution. NORMINV in Excel stands ready to assist, unraveling the complexities of inverse normal cumulative distribution calculations with ease and precision. This function proves indispensable for those navigating statistical analyses, risk assessments, or any scenario involving normal distributions. To employ NORMINV effectively, provide it with the desired probability for which you need the corresponding value. You also furnish the mean (average) and standard deviation values characterizing the normal distribution. Once armed with these inputs, NORMINV diligently computes the value associated with the specified probability, offering insights into the distribution's characteristics and aiding decision-making in statistical models and financial projections.

## Examples

Suppose you have a standard normal distribution with a mean of 50 and a standard deviation of 10. You want to find the value associated with a probability of 0.75. The NORMINV formula would be: =NORMINV(0.75, 50, 10) This will return the value in the distribution corresponding to the probability of 0.75.

Consider a scenario with a mean of 0 and a standard deviation of 1. You aim to determine the value corresponding to a probability of 0.05. The NORMINV formula would be: =NORMINV(0.05, 0, 1) This calculation reveals the value in the standard normal distribution for the probability of 0.05.

## Notes

The NORMINV function assumes a standard normal distribution with a mean of 0 and a standard deviation of 1 if the mean and standard deviation parameters are omitted. Ensure to adjust the function inputs based on the specific normal distribution characteristics relevant to your analysis or scenario.

## Questions

How does the NORMINV function determine the value corresponding to a given probability?

The NORMINV function calculates the value associated with a probability in a standard normal distribution using the inverse of the cumulative distribution function for the normal distribution. It essentially finds the outcome that corresponds to the specified probability based on the mean and standard deviation provided.

Can the NORMINV function work with non-standard normal distributions?

No, the NORMINV function is designed to operate on standard normal distributions with a mean of 0 and a standard deviation of 1. If working with non-standard distributions, make sure to adjust the mean and standard deviation parameters accordingly before using NORMINV.

What happens if I omit the mean and standard deviation parameters in the NORMINV function?

If you omit the mean and standard deviation parameters in the NORMINV function, Excel will assume a standard normal distribution with a mean of 0 and a standard deviation of 1 by default. Make sure to specify the mean and standard deviation values if your distribution deviates from these standard parameters.