Calculate difference between two rows in a matrix

Hi SARAHCH 

Please try this:

First of all, I create a set of sample:

Then add a new table, the value of the table is the field you want to show in the matrix:

Table 2 = {"2022","2023","Variance"}

Then add a measure:

Measure = 
VAR _newValue = SELECTEDVALUE('Table 2'[Value])
RETURN SWITCH(
    _newValue,
    "2022",CALCULATE(SUM('Table'[value]),YEAR('Table'[Date])=2022),
    "2023",CALCULATE(SUM('Table'[value]),YEAR('Table'[Date])=2023),
    "Variance",CALCULATE(SUM('Table'[value]),YEAR('Table'[Date])=2023)-CALCULATE(SUM('Table'[value]),YEAR('Table'[Date])=2022)
)

The result is as follow:

If the above one can't help you, could you please provide more raw data in your tables (exclude sensitive data) with Text format and your expected result with backend logic and special examples? It would be helpful to find out the solution. You can refer the following links to share the required info:

How to provide sample data in the Power BI Forum

How to Get Your Question Answered Quickly

And It is better if you can share a simplified pbix file. You can refer the following link to upload the file to the community. Thank you.

How to upload PBI in Community

Best Regards

Zhengdong Xu
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