Power BI and DAX, with the numbers checked
Each guide builds one real report against one real dataset. The DAX is written out in full. The dataset downloads with the guide. The numbers the guide says the measures return were computed independently before publication. If a number cannot be checked, the guide does not ship.
Latest guides
Power BI year-over-year sales: a DAX measure that returns the right prior-year number
Three measures — Total Sales, Sales PY, YoY % Change — on a calendar table. October 2025 comes out at $13,436 against $10,995 a year earlier: +22.2%.
GUIDE 02 · DAX · RUNNING TOTAL + RANKPower BI running total and category rank in DAX, with no helper columns
One CALCULATE measure for the running total, one RANKX measure for the category rank. The 2025 running total reaches $122,707 by October; Desks ranks first.
How a guide is checked
Every guide names the software it was verified with and the exact results the measures must return. The measure results are computed a second way — the same aggregations run in Python against the same CSV — and the guide only publishes when the two agree to the cent. The Method page states what was and was not run, including the fact that the Power BI Desktop interface steps were not run on this machine.