With my experience of using Power BI, many users want to insert a sum row into the data table instead of using the grand total feature in the table/matrix visual. However, Power BI does not support inputting rows into columns by DAX method. Therefore, I would like to introduce the way to insert rows in query editor with further extension of adding multiple rows to sum up the previous N days’ data. It is important to note that the method is only suitable if you would like to insert roles to the existing column. As the result, the date hierarchy would become invalid that may affect the creation of report, this is because adding the sum rows would change the column type from Date/Time to Text.
Insert Sum Rows For Dynamic Period.pbix