Powerbi DAX formula for calc previously date

Question

i have data set from my Azure DevOps (collect data with work items, state, date etc...) and i want calculate count of work item from previously date. It's necessary what calculate grown rate (current count of work items - count of work items from previously date) and create visualisation.

Data set format (example): field# (1) work item id (2)Date) ...

Graph Example (as is):

Graph Example (to be):

Example of raw data:

Answer 1

Can I consider these below you sample raw data? I will delete this answer after everything is clear.

date        work item id
9/24/2020   1012
9/24/2020   1013
9/24/2020   1014
9/25/2020   1012
9/25/2020   1013
9/25/2020   1014
9/25/2020   1015
Gap in date
9/27/2020   1012
9/27/2020   1013
9/27/2020   1014
9/27/2020   1015
9/27/2020   1016
9/27/2020   1017

If I consider Date wise ID count, below is the result-

date        id count
9/24/2020   3
9/25/2020   4
9/27/2020   6

Now what you want from the above counts? As per my understanding-

date        diff
9/24/2020   3 ->> As no previous date available, its current date count
9/25/2020   1 ->> Diff between current and previous date
9/27/2020   ? ->> what you wants here? as previous date is not there