how about some power query functions: running total function, offset function, geometric mean

This is for Miguel! Please make running totals/cumulated totals a standard functionality in Power BI like it is in PowerPivot (right click - display result as running total in...). It is not user friendly with DAX formulas. If you search for "cumulative totals" and "running totals" in the improvement ideas you will see that it appears several times under different headings. So the votes should be cumulated and thus get higher priority.