Calculate difference between values in the same column

Try Earlier function

https://community.powerbi.com/t5/Desktop/Explanation-of-the-EARLIER-formula/td-p/529469

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Thanks.

My Recent Blog - https://community.powerbi.com/t5/Community-Blog/Comparing-Data-Across-Date-Ranges/ba-p/823601

Hi Resh,

You could try to use below measure to get difference between each month.

trend = SUM('Table (2)'[Value])-CALCULATE(SUM('Table (2)'[Value]), FILTER(ALLEXCEPT('Table (2)','Table (2)'[Project]),MONTH('Table (2)'[Date])=MONTH(MIN('Table (2)'[Date]))-1))

Best Regards,
Zoe Zhi

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