## How does the POISSON.DIST function (DAX) work?

The POISSON.DIST function (DAX) calculates the Poisson probability mass function.

## POISSON.DIST Formula Syntax

POISSON.DIST(
x,mean,cumulative
)

## How do you use the POISSON.DIST function?

A common application of the Poisson distribution is predicting the number of events over a specific time, such as the number of cars arriving at a toll plaza in 1 minute.

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## Considerations when using the POISSON.DIST function

If x is not an integer, it is rounded.

If x or mean is nonnumeric, POISSON.DIST returns the #VALUE! error value.

If x < 0, POISSON.DIST returns the #NUM! error value.

If mean < 0, POISSON.DIST returns the #NUM! error value.

POISSON.DIST is calculated as follows.

For cumulative = FALSE:

For cumulative = TRUE:

## Formula examples using the POISSON.DISTfunction

=POISSON.DIST(C5,C6,FALSE)

=POISSON.DIST(B5,B6,TRUE)

=POISSON.DIST(A2,A3,FALSE)