If you have spent years writing formulas across cell ranges in a spreadsheet, this episode is the reset. We add Product Selling Price from the semantic model, then create a formula measure called Units Actual - Revenue Actual divided by Product Selling Price - set as a visual measure with Sum on the column and formula execution on every row. The point is the engine: you select measure objects, not ranges or arrays, and one expression fills the whole grid, grand total included.
