Sequential numbering formula omitting 0's and resetting after X rows

I have a series of data that is hundreds of rows. I have attached a sample file. In column E I want an "ID" that starts at 1 and sequentially numbers skipping any 0 values that are in column D. I was able to accomplish that with the below formula:

Formula:

=IF(D2=0,"",COUNTIF($D$2:$D2,">0"))

The part that I haven't been able to figure out is that I want the numbering to "reset" after a specific number of rows. The number of rows will be specified by a cell. In my example file, cell J1 indicates that the count should reset after 15 rows. I have also included what the desired result should look like in column F.

Any help would be greatly appreciated.

Thanks for the response! I would be ok using either the number OR the change in inventory number, but I am uncertain how to accomplish it that way either.

I came up with the same as Ali, before seeing her response, i.e. in E2:

=IF(D2=0,"",COUNTIFS($D$2:$D2,">0",A$2:A2,A2))

Copy down as required.

Pete

Thank you very much. That worked perfectly!!

Agh!! I got 3 email notifications of Post #7 - hope the troubles are not starting up again.

Pete