Business Intelligence with Power BI

L05 · DAX I: Measures

Practice — Medium · Solution

Task-by-task

  1. Avg Units per Order = DIVIDE ( [Total Units], [Order Count] )3.033 (259,421 ÷ 85,538). Pure composition: two existing measures and a safe division. No new iteration was needed because both ingredients already existed as answers.
  2. Avg Line Profit = AVERAGEX ( Sales, Sales[Quantity] * ( Sales[UnitPrice] * ( 1 - Sales[DiscountPct] ) - RELATED ( Products[UnitCost] ) ) ). The identity: an average is the sum divided by the count, so Avg Line Profit × 165,042 lines must reproduce Gross Profit ($38,714,371.79) to within rounding. If yours does not, the per-row expression differs from the one inside Total Cost/Total Revenue — same math, or the identity breaks. Free consistency checks like this are how measure families audit themselves.
  3. Three sorts, verified: Revenue: Furniture leads ($24.80M). Profit dollars: Furniture still leads — its revenue bulk outweighs its thin margin. Margin %: Decor leads (63.95%), Furniture last (55.56%).
  4. Gross Profit crowns Furniture: profit dollars = revenue × margin, and Furniture's $24.80M at 55.56% (~$13.8M of profit) beats Decor's $5.02M at 63.95% (~$3.2M). A high percentage of a small number lost to a low percentage of a huge one — the columns explain each other, which is why the table shows all three.

Reflection answers

  • The decider: whether the answer's ingredients already exist as measures. Basket size divided two finished answers. Average line profit needed arithmetic inside each row before any aggregation — per-row math means an iterator's row context, every time.
  • The honest first response is a question back: "best by which measure? Revenue and profit dollars say Furniture; margin rate says Decor — and they lead for different reasons." Third appearance of the course's oldest lesson: units crowned Lighting in Lesson 1, dollars crowned Furniture, margin crowns Decor. The measure defines the winner; the analyst names the measure.