Glossary
Yield
Yield is how much fabric a marker consumes per garment, and marker efficiency is the percentage of the laid cloth that ends up inside a pattern piece.
Efficiency in the mid-eighties is respectable for a shirt; tailoring with a nap or a large repeat runs lower. The remainder is offcut, and at production volume it is the difference between a style making money and not.
Yield is quoted per garment and per size, because a run weighted toward the larger sizes uses more cloth than the average implies.