QueryAndChart Power BI and DAX tutorials built on real data, with every measure result checked before publication. 2026-11-10T00:00:00-07:00 https://queryandchart.com/ Power BI year-over-year sales: a DAX measure that returns the right prior-year number https://queryandchart.com/guides/year-over-year-sales/ 2026-11-10T00:00:00-07:00 Three DAX measures on a calendar table: Total Sales, Sales PY with SAMEPERIODLASTYEAR, and YoY % Change. October 2025: $13,436 against $10,995 a year earlier, +22.2%. Results verified by identical aggregation in Python against the same CSV. Power BI running total and category rank in DAX, with no helper columns https://queryandchart.com/guides/running-total-rank/ 2026-11-10T00:00:00-07:00 One CALCULATE measure for the running total and one RANKX measure for the category rank. The 2025 running total reaches $122,707 by October; Desks ranks first at $56,959. Results verified by identical aggregation in Python against the same CSV.