How it's calculated: Price ÷ (Qty × unit size) gives price per base unit. Yield % is the usable share of what you buy — under 100% for roll ends or trim/bleed loss; leave at 100% if the whole thing is usable. Wastage % is a buffer on top for what you can't predict — misprints, colour-calibration sheets, torn stock. Both are set per item. Inflation is set once, above the table, and applies as a single blanket rate to every item's True Cost — a forward buffer for supplier price rises, not something that varies item to item.
For material priced by the sheet, pick sheet or ream (500 sheets) and set Qty to the sheet count. For large-format material sold by the roll — vinyl, canvas, flex banner — pick sqm or sqft and set Qty to the roll's total area (width × length), not the roll count. For something bought as one box or pack that yields a fixed count — a box of lanyard clips, a pack of zip ties — pick piece and set Qty to the count.
In a print job: Amount is per single unit of the run — 1 sheet per flyer, or 0.1 sheet if you fit 10-up on one A4 sheet. Setup / plate cost is a one-time cost for the job — machine setup, plate-making, die-cutting — divided by Quantity to give a cost per unit, added to materials cost before the target price is worked out. Quantity also turns that per-unit target price into a whole-job quote.
Quick glossary: GSM — grams per square metre, how paper weight is measured (higher = thicker). Ream — 500 sheets. Bleed — artwork printed slightly past the trim line so there's no white edge after cutting. Substrate — the material being printed on (paper, vinyl, canvas, fabric). Setup / plate cost — the fixed cost to prepare a job before the first unit prints, independent of how many units you make.