create a table for price difference

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Step 1: Load Data
Load your data into Power BI. You should have two tables: Table1 and Table2.

Step 2: Create Relationships
Ensure there is a relationship between Table1[Reference] and Table2[Reference].

Step 3: Create Calculated Columns
In Table1, create the following calculated columns:

ATA Mapping Model Column:

ATA Mapping Model =
LOOKUPVALUE(
Table2[ATA mapping model],
Table2[Reference], Table1[Reference]
)

ATA Price Column:

ATA Price =
LOOKUPVALUE(
Table1[Price],
Table1[Reference], Table1[ATA Mapping Model]
)

Step 4: Create the Measure for ATA Price Difference
Create a measure to calculate the ATA price difference:

ATA Price Difference Measure:

ATA Price Difference =
DIVIDE(
MAX(Table1[ATA Price]),
MAX(Table1[Price])
)
Step 5: Create the Visual
Add a table visual to your report.
Add the Prefix column from Table2 and the ATA Price Difference measure to the table visual.
Apply a filter to the visual to show only rows where Retailer is "H&M".