Calculate delta using slowly changing dimensions

You can create measures like

Products = 
VAR CurrentDate = MAX( 'Date'[Year month] )
VAR Result = CALCULATE(
	COUNTROWS( 'Table' ),
	'Table'[Start date] <= CurrentDate
		&& 'Table'[End date] > CurrentDate
)
RETURN Result

Newly Added = 
VAR CurrentDate = MAX( 'Date'[Year month] )
VAR Result = CALCULATE(
	COUNTROWS( 'Table' ),
	'Table'[Start date] = CurrentDate
)
RETURN Result

Removed = 
VAR CurrentDate = MAX( 'Date'[Year month] )
VAR Result = CALCULATE(
	COUNTROWS( 'Table' ),
	'Table'[End date] = CurrentDate
)
RETURN Result

Delta = [Newly Added] - [Removed]

Hi Janou ,

Thank you johnt75 , for your excellent response! Your approach effectively captures newly added, removed, and delta values per month. 

I’d like to expand on this with a small refinement to ensure products that end within the same month are correctly counted when calculating active products.

1.To ensure proper time intelligence calculations, first create a Date Table:

If our answer meets your requirement,consider accepting it as solution.

Thank you for being a part of Microsoft Fabric Community Forum!

Regards,
Pallavi.

Hi Janou ,

As we have not received a response from you yet, I would like to confirm whether you have successfully resolved the issue or if you require further assistance.

If the issue has been resolved, please mark the helpful reply as a "solution" to indicate that the question has been answered and to assist others in the community.
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