A supplier scorecard should help a buyer decide what to discuss, what to change and where a backup source is needed. Start with four measures: fill rate, delivery reliability, price variance and substitutions. Keep the underlying orders visible so the score is explainable.
Choose a period and preserve the original promise
Use a period long enough to include representative orders and show the sample size. Five orders can expose a problem, but they cannot establish a stable long-term reliability estimate. Report missing receipts or unverified prices instead of silently excluding them.
Record both the original order and accepted changes. Measuring only against a revised promise hides what changed. Measuring only against the original request can unfairly classify a buyer-approved schedule change as supplier failure. Show both where the distinction matters.
1. Fill rate: units and lines are different
For an item with one consistent unit:
Unit fill rate = accepted original-item units received / original-item units ordered × 100
Define the measurement cutoff and how you treat permitted substitutes. For a mixed catalog, avoid adding incomparable units such as kilograms, bottles and pallets into a misleading single ratio. Use item-level rates, a consistently defined line-fill measure, or a disclosed weighting method.
An illustrative order for 100 bottles with 90 accepted bottles has 90% unit fill. That does not mean five of fifty SKUs were missing: a unit rate cannot establish the number of affected lines.