PPC — Percent Plan Complete
PPC is the single metric that keeps the Last Planner System honest. It measures how often last planners deliver what they committed to for the week — not what the master schedule said should happen, not what status reports show as in progress, but which commitments actually closed as promised. One ratio, one honest view of how reliably a project is running.
What is PPC?
PPC (Percent Plan Complete) is the reliability metric used in the Last Planner System to measure the percentage of weekly commitments made by last planners that are actually completed as promised by the end of the committing week.
Also known as: Percent Promises Complete, plan reliability, weekly commitment reliability. The acronym PPC is standard across the lean construction literature; the full name varies slightly between sources.
The PPC formula
PPC is deliberately simple so it cannot be gamed by weighting or partial credit. One commitment, one answer: done as promised, or not.
PPC = (commitments completed as promised ÷ commitments made) × 100
- Commitments made: only the activities the last planners agreed to deliver in the committing week. Not everything in the master schedule for that week — only what was explicitly committed.
- Completed as promised: finished in full, to the agreed handoff condition, within the committing week. Partial completion does not count. A task 80% done at week end is 0, not 0.8.
- Rounding: report to the nearest whole percent. The trend matters, not the decimal.
What a good PPC score looks like
Benchmarks from the LPS literature and from mature lean programmes across data centres, infrastructure and commercial building:
| PPC band | What it usually means | First place to look |
|---|---|---|
| Under 50% | Commitments are closer to a wishlist than a plan. Last planners are not screening against reality. | Lookahead and make-ready — constraints are not being cleared before the committing week. |
| 50–70% | A programme that is running on luck. Half the committed work is depending on something being made ready on the fly. | Make-ready action list — who owns clearing each open constraint? |
| 70–75% | Make-ready is working but handoff conditions are inconsistent. The plan is improving. | Trade handoff definitions — are both sides agreeing the same condition? |
| 75–85% | A mature LPS programme. The learning loop from reason codes is actually feeding the next lookahead. | Nothing. This is the healthy band — focus on reason-code trends. |
| Above 90% (sustained) | Teams are under-committing. The visible metric looks great but committable work is being withheld to protect the number. | Culture — PPC is a reliability measure, not a performance incentive. |
Reasons for non-completion — the real value of the metric
The PPC number tells you how reliable a week was. The reason codes tell you why. Over time the reason-code trend is more valuable than the PPC number itself, because it tells the team which constraint category is systematically breaking commitments.
Design
RFIs unanswered, drawings late, submittals not approved, coordination clash discovered late.
Materials
Procurement slip, delivery missed, site storage full, wrong SKU.
Prerequisite
Upstream trade did not clear to the agreed handoff condition in time.
Equipment or labour
Crew pulled to another priority, plant unavailable, inspector slot missed, certification lapsed.
Change
Scope change, client decision pending, weather, late variation instruction.
Other (should be rare)
Catch-all. If “other” is ever the top reason, the categories need refining — a trend you cannot name is a trend you cannot fix.
Worked example: a Friday PPC on a commercial fit-out
A commercial fit-out team committed to ten activities for the committing week. The Friday review walks each one and computes a single PPC number — plus a reason-code mix that becomes the agenda for Monday's lookahead.
| Commitment | Done? | Reason if not |
|---|---|---|
| Partition framing, zone 1 | Yes | — |
| Partition boarding, zone 1 | Yes | — |
| Ceiling grid, zone 2 | No | Prerequisite — MEP first-fix overran |
| MEP first-fix, zone 2 | Yes | — |
| Painter prep, zones 1–2 | Yes | — |
| First coat, zone 1 | Yes | — |
| Flooring delivery, zone 3 | No | Materials — logistics slot missed |
| Snagging walk, zone 1 | Yes | — |
| Door hanging, zone 1 | No | Design — ironmongery schedule rev C pending |
| Cleaning handover, zone 1 | Yes | — |
PPC = 7 completed ÷ 10 committed = 70%
The number is below the healthy band — but it is the reason mix that drives next week's improvement. Of three misses: one was a prerequisite failure (ceiling grid blocked by MEP overrun), one a materials failure (delivery slot missed), and one a design failure (ironmongery schedule awaiting rev C). All three were in theory visible in the lookahead the Monday before, which means the lookahead screening missed them. Monday's lookahead now opens with the question: “why did we not catch these three constraints on the previous screen?”
Four consecutive weeks of “design” being the top reason, and the project knows the design coordination process needs attention — not individual activities and not individual trades.
Where PPC fails as a standalone metric
PPC does one thing well — measure commitment reliability — and nothing else. Treating it as a project health scorecard produces predictable failure modes.
PPC without reason codes is a vanity number
A trend line of 78%, 81%, 75%, 83% tells leadership almost nothing. The same four weeks with reason codes — three design misses, two materials, one prerequisite — tells the lookahead team exactly where to focus.
Using PPC as a performance target
Last planners who are rewarded for high PPC under-commit. Last planners who are punished for low PPC refuse to log misses honestly. In both cases the number stops reflecting reality. PPC is a diagnostic, not a KPI to pay against.
Project-level only, no trade or team breakdown
A 76% project PPC can be hiding a 95% from one well-run trade and a 55% from a trade that is quietly failing every week. PPC by trade and by phase is where the diagnostic lives.
PPC not fed back into the lookahead
If this week's PPC and reason-code trend do not open next Monday's lookahead meeting, the learning loop is broken and the metric is being collected for no reason.
How VisiLean computes and feeds back PPC
PPC in VisiLean is not a report pulled on Friday afternoon — it is computed continuously as last planners update completion from LiveSite in the field. The reason-code trend is visible in the lookahead meeting the following Monday, so the metric drives action instead of archiving it.
- Weekly commitments made in the Last Planner workflow are tracked on the same schedule that drives the CPM master — no separate PPC spreadsheet, no manual roll-up.
- Last planners mark commitments complete and attach reason codes to misses from LiveSite, the same mobile app that captures field progress and photo updates.
- Teams use the resulting reason-code trend to shape the next week's lookahead, letting the top category change the screening priority rather than being reviewed after the fact.
- Trailing-weeks PPC and reason-code mix are visible to the project team as the field data accumulates, so the trend is seen alongside the current number.
- Because the master, the lookahead and the weekly commitment set are three views of the same schedule, the metric and the plan do not drift as a project runs.
Related methods
Last Planner System
The production-control system PPC is the metric for. The five conversations, worked examples and how the LPS loop fails when PPC is skipped.
Read moreLookahead Planning
The screening step that largely determines next week's PPC. Low PPC is almost always the symptom of lookahead failures.
Read morePull Planning
Where the sequence PPC measures against is actually agreed. Pull decides what; lookahead decides whether; PPC measures how well.
Read moreVisiLean Planner
The product that computes PPC continuously from field updates and feeds the trend into the following week's lookahead.
Read moreFrequently asked questions
What is PPC in construction?
PPC stands for Percent Plan Complete. It is the reliability metric used in the Last Planner System to measure how often weekly commitments made by last planners are actually completed by the end of the committing week. The formula is: PPC = (number of commitments completed as promised ÷ number of commitments made) × 100.
What is a good PPC score?
Industry benchmarks established in the LPS literature are: 50–70% is unreliable (make-ready is broken), 70–75% is improving, 75–85% is a mature programme, and sustained scores above 90% usually indicate the team is under-committing to flatter the metric rather than genuinely delivering more. The absolute number matters less than the trend and the reason-code mix underneath it.
How do you calculate PPC on a weekly plan?
Count the number of commitments the last planners made for the committing week. Count how many of those were completed in full by the end of the week — partial completions do not count. Divide completed by committed and multiply by 100. PPC is calculated per team or per trade for diagnostics, and rolled up to a single project-level PPC for the leadership view.
What are the standard reasons for a missed PPC commitment?
Most LPS implementations use five or six standard categories so trends can be read week over week: design (RFIs, submittals, drawings), materials (procurement, delivery, logistics), prerequisite work (upstream trade incomplete), equipment or labour (crew, plant, skills), and change (scope, weather, client decision). An “other” category exists but should rarely be the top reason — if it is, the categories need refining.
Why can a 95% PPC score be a bad sign?
A score sustained above 90% usually means the team is committing only to work they are certain to complete and leaving a buffer behind the number. The visible metric looks great, but the project is slowly losing weeks of productivity because committable work is being held back out of fear of the PPC meeting. The fix is cultural — PPC is a reliability measure, not a performance incentive. The healthiest mature teams run at 75–85% and treat the missed share as the input to next week's lookahead.
See PPC computed from live field updates
VisiLean calculates PPC continuously as last planners update completion from the field, and feeds the reason-code trend into the following week's lookahead meeting automatically.