Hi,

For column E I used

=DATEDIF(C2,D2,"d")

to calculate the difference in days then for the first quartile the ARRAY
formula

=AVERAGE(IF(E2:E19<"",IF(E2:E19<=QUARTILE(E2:E19, 1),E2:E19)))

This is an array formula which must be entered by pressing CTRL+Shift+Enter
'and not just Enter. If you do it correctly then Excel will put curly brackets
'around the formula {}. You can't type these yourself. If you edit the formula
'you must enter it again with CTRL+Shift+Enter.

Mike

"Rum" wrote:

Here is a scenario:

If:
Column A is list of AUTO MAKERS
Column B is list of DEALERSHIPS
Column C is list of dates when DEALERSHIP OPENED
Column D is list of dates when DEALERSHIP READY TO SELL CARS
Column E is the the difference of Column D and Column C (D-C) (Cycle Time)

There are a thousand rows and multiple column in this data set.

I would like to find out how long does it take the 25th percentile of any
DEALERSHIP to get READY TO SELL CARS.

Please share your thoughts.

Rum