Hi , @sondhboyz
According to your description, you want to "Difference in new row when i change the year or month or slicer".
First of all, if you want to insert a difference in each row in Matrix and be affected by the slicer, which is difficult to achieve in Power BI, you need to build a new dimension table that contains the difference names of your different rows . Then use metrics to achieve your needs.
If you don't need a slicer, you can also refer to the following blog:
Difference between two rows in Power BI - Analytics Tuts (analytics-tuts.com)
Calculate difference between two rows in Power BI - Bing video
If you only need to calculate the difference between the two head and tail dates of the slicer, you can use the MAX() and MIN() functions to get the selection value of the slicer, and then create a virtual table to get the values corresponding to the year and month, and then subtract them.
If this method does not meet your needs, you can provide us with your special sample data and the desired output sample data in the form of tables, so that we can better help you solve the problem. (You can also upload you sample .pbix [without sensitive data] to the OneDrive and share with the OneDrive link to me ! )
Thank you for your time and sharing, and thank you for your support and understanding of PowerBI!
Best Regards,
Aniya Zhang
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