Total Cost is the per-unit production cost of the recipe: for the default portion it is the recipe's production price; for other portion sizes it is the cost price stored on that portion. If you have not entered ingredient costs or a production price on the recipe (or on that portion), the cost is zero and the Profit Margin and Total Profit columns simply equal the sale price. Update the recipe's costs and the report recalculates on the next load. Importing supplier receipts to auto-calculate food costs also feeds this figure.