Often people have problems with spaces in the abbreviations when importing data in Power BI Desktop. The sample data and the expected result are first provided below for the reader's reference.
In Power BI, we sometimes meet cumulative problem. For basic direct accumulation we could use Dax language or M language. But for conditional accumulation and group conditional accumulation, we tend to use M language. The following will be divided into three cases to gradually explore the cumulative summation.