First pass yield (FPY)

First pass yield measures the proportion of units that complete a process step correctly on the first attempt, without repair, rework, retesting or scrap. It reveals quality losses that final output counts can hide.

When to use it

• Answer the key performance question: “How efficient are our internal operational processes?”
• Assess this KPI within the Operational processes and supply chain perspective.
• Plan data collection, formula use, reporting frequency, and data-source requirements for this KPI.
• Compare results against the targets, benchmarks, examples, or trend guidance available for this KPI.

Origins

FPY grew from the quality-control principle of producing conforming output correctly the first time. Its lineage runs through statistical process control, total quality management, lean production and Six Sigma rather than one inventor. The measure counters final yield, which may count a repaired item as successful and thereby conceal extra labour, delay, material and capacity consumed by the initial failure.

What it is

Perspective: Operational processes and supply chain perspective.

Key performance question: How efficient are our internal operational processes?

At a single step, FPY compares units that pass the first time with all units entering that step. A failure remains a first-pass failure even if an employee immediately fixes it and the unit ultimately ships.

For a sequence of steps, multiplying step yields produces rolled throughput yield: the estimated probability that a unit passes the entire flow without first-pass failure. Averaging step percentages is generally inappropriate because it does not represent that cumulative probability.

The measure requires explicit conformance criteria and process boundaries. It can be applied to physical products, transactions or service cases, provided entry, success and rework are observable on a common basis.

How to use it

Measurement

Map the process into meaningful steps. For each, define a unit, the specification for first-pass success, the point of entry and every activity that counts as rework, repair or retest.

Data collection method