EXPONDIST

EXPONDIST(x, lambda, cumulative)

Returns the probability distribution function OR the cumulative probability function for an exponential distribution.

x	The value of the function.
lambda	The parameter value.
cumulative	A logical value indicating the type of function to use: False (or 0) = individual probability (equal to) True (<> 0) = cumulative probability (equal to or less than)

REMARKS

* This function is only available for backwards compatibility and should not be used.
* EXPON.DIST was added in Excel 2010 to replace this function.
* The exponential distribution is a continuous distribution
* If "x" < 0, then #NUM! is returned.
* If "x" is not numeric, then #VALUE! is returned.
* If "lambda" = 0, then #NUM! is returned.
* If "lambda" is not numeric, then #VALUE! is returned.
* If "cumulative" = False, then the height of the curve at "x" is returned.
* If "cumulative" = True, then the area under the curve to the left of "x" is returned.
* For the Microsoft documentation refer to support.microsoft.com

	A
1	=EXPONDIST(0.2, 10, TRUE) = 0.865
2	=EXPONDIST(1, 4, 1) = 0.982
3	=EXPONDIST(0.2, 10, FALSE) = 1.353
4	=EXPONDIST(0.2, 0, FALSE) = #NUM!
5	=EXPONDIST(5, "some text", FALSE) = #VALUE!