Sum previous available data based on filtered data

[jaimeoconor]

Hi,

I have, for example, the following data (date field format is 'DD/MM/YYYY'):

Date               Sales

28/6/2019    85

4/7/2019       105

12/7/2019     90

17/7/2019     70

26/7/2019      120

Imagine data is filtered by 26/7/2019. I would like to create a table with:

- Filtered date Sales (=sum(Sales)). Expected outcome: 120

-Previous available Date Sales(Any idea?). Expected outcome: 70 

-Four previous available Date Sales (Any idea?). Expected outcome: 85

Many thanks in advance!