RANGE SUM per product on the three previous values

[lotitolo]

Hi
I would like to be able to calculate the sum of the three previous days as in the example below where I can estimate the total sales over the last three days by product...

I have already started to make a first formula just to sum the last three values, and it works well:

RangeSum(above(TOTAL Sum(Sales),0,3))

Where I have trouble is to get the sum of the last three days but by product, it does not work with this formula:

RangeSum(above(TOTAL Sum({<Product}Sales),0,3))

Below, here is what the result should look like

DATE	Product	Sales	Last 3 days sales
01/01/2019	APPLE	2	2
01/01/2019	ORANGE	1	1
01/01/2019	BANANA	10	10
02/01/2019	APPLE	1	3
02/01/2019	ORANGE	1	2
02/01/2019	BANANA	20	30
03/01/2019	APPLE	4	7
03/01/2019	ORANGE	2	4
03/01/2019	BANANA	10	40
04/01/2019	APPLE	4	9
04/01/2019	ORANGE	4	7
04/01/2019	BANANA	5	35
05/01/2019	APPLE	4	12
05/01/2019	ORANGE	10	16
05/01/2019	BANANA	1	16

Here is the source file attached,

Thank you very much.

[Tomas · Accepted solution]

Hi @lotitolo,

 this should help: 

Aggr(RangeSum(above(sum(Sales),0,3)),Product,DATE)

Extremely important here is order of dimension in arguments. Because

Aggr(RangeSum(above(sum(Sales),0,3)),DATE,Product)

will give you unwanted result thanks to different ordering

[lotitolo]

Thank you very much, this solution works perfectly!