Need help with with tabel Power Query

Hi hansreivers TRy this 

1. In Power Query, create a conditional column:

Margin = if [Article] = "x" then [Costprice] * 0.15 else 0

• In Power BI, add a calculated column:

TotalPrice = [Salesprice] + [Margin]

• Use a mapping table for dynamic updates, or a DAX measure:

DynamicMargin = IF(SELECTEDVALUE('Table'[Article]) = "x", SUM('Table'[Costprice]) * 0.15, 0)

If this post helped please do give a kuods and accept this as a solution
Thanks In Advance 

Hi hansreivers Then you can add a log table with Article, Effective Date, and Increment columns. Load it into Power BI and create a dynamic margin measure using DAX:

DynamicMargin = 
VAR Increment = 
    CALCULATE(
        MAX('LogTable'[Increment]),
        FILTER(
            'LogTable',
            'LogTable'[Article] = 'SalesTable'[Article] &&
            'LogTable'[Effective Date] <= 'SalesTable'[Date]
        )
    )
RETURN 'SalesTable'[Costprice] * Increment