A text index of the 14 domains, 34 calculators and 103 metrics on this page. Every figure computes in your browser; open the page with JavaScript enabled for the working instruments.
- 01 — Earned Value Management
- 02 — Budget & Burn Rate
- 03 — Estimation
- 04 — Schedule & Critical Path
- 05 — Schedule Compression
- 06 — Resources & Team
- 07 — Communication
- 08 — Risk
- 09 — Decision Analysis
- 10 — Quality & Six Sigma
- 11 — Project Selection & Finance
- 12 — Procurement & Contracts
- 13 — Agile Forecasting
- 14 — Lean & Flow
01 — Earned Value Management
One integrated system that answers three questions at once: are we on budget, are we on schedule, and where will we land at completion? It works by comparing what you planned to spend, what you actually spent, and the value of the work actually finished.
EVM — PMI Practice Standard; Lipke, “Schedule is Different.”
01.1 — Earned value core & forecasting
CV · SV · CPI · SPI · EAC · ETC · VAC · TCPI
Enter the four base measures below and every earned-value metric updates live. The performance metrics describe project health today; the forecasting metrics project that health forward to completion. All monetary figures share whatever currency you enter.
Full analysis
CV = EV − AC SV = EV − PV
CPI = EV ÷ AC SPI = EV ÷ PV
EAC = BAC ÷ CPI ETC = EAC − AC
VAC = BAC − EAC
TCPI = (BAC − EV) ÷ (BAC − AC)
Parameters
- BAC — Budget at Completion
- The total approved budget for all project work. The baseline everything else is measured against.
- e.g. 100000
- PV — Planned Value
- The budgeted cost of the work that was scheduled to be done by now (also called BCWS).
- e.g. 50000
- EV — Earned Value
- The budgeted cost of the work actually completed so far: % complete × BAC (also called BCWP).
- e.g. 45000
- AC — Actual Cost
- What the completed work really cost, regardless of what was budgeted (also called ACWP).
- e.g. 60000
- EAC — management forecast (optional)
- A forecast you have committed to, if it differs from BAC ÷ CPI. Only TCPI — to hit EAC uses it; leave blank to read that line against the calculated EAC.
- e.g. 125000
Results
Performance today
- Cost Variance (CV)
- Budget health in currency: value earned minus money spent.
- Schedule Variance (SV)
- Schedule health expressed in currency: work done minus work planned.
- Cost Performance Index (CPI)
- Cost efficiency: value earned per unit of money spent.
- Schedule Performance Index (SPI)
- Schedule efficiency: rate of progress versus the plan.
- Cost–Schedule Index (CSI)
- CPI × SPI — a single overall-health number; hard to recover once it drops far below 1.
- % Complete
- Share of the total scope actually finished: EV ÷ BAC.
- % Spent
- Share of the total budget already consumed: AC ÷ BAC.
Forecasting completion
- EAC — typical variance
- BAC ÷ CPI. Forecast final cost assuming today’s cost efficiency continues — the default assumption.
- EAC — atypical variance
- AC + (BAC − EV). Use when the variance was a one-off and the remaining work will go to plan.
- EAC — cost & schedule
- AC + (BAC − EV) ÷ (CPI × SPI). Use when schedule pressure is also driving cost (e.g. a hard deadline).
- ETC — Estimate to Complete
- EAC − AC (using the typical-variance EAC). Money still needed to finish the remaining work.
- VAC — Variance at Completion
- BAC − EAC (using the typical-variance EAC, BAC ÷ CPI). The over- or under-run expected on the day the project finishes.
- TCPI — to hit BAC
- (BAC − EV) ÷ (BAC − AC). The cost efficiency you must sustain on all remaining work to still land on the original budget.
- TCPI — to hit EAC
- (BAC − EV) ÷ (EAC − AC). The efficiency needed to hit a revised forecast instead of the original budget. Against the calculated EAC of BAC ÷ CPI this reduces to CPI itself, so it only becomes an independent test once you enter a management forecast above.
Charts
- Cost position
- What was planned, what was earned, what it cost — against the budget line.
- CPI–SPI quadrant
- Cost efficiency against schedule efficiency, crossed at 1.00.
- TCPI required efficiency
- The cost performance the remaining work must sustain to still hit BAC.
01.2 — Earned Schedule
ES · SV(t) · SPI(t) · IEAC(t)
SPI can look healthy late in a project because PV is running out. Earned Schedule puts EV back on the time axis. This card assumes LINEAR PV — the useful, explicit approximation for a four-input reading. Treat IEAC(t) as a trend, not a committed finish date.
Full analysis
ES = PD × (EV ÷ BAC)
SV(t) = ES − AT
SPI(t) = ES ÷ AT
IEAC(t) = PD ÷ SPI(t)
Parameters
- BAC — Budget at Completion
- Total approved budget for the complete scope. Currency; must be greater than 0.
- e.g. 200000
- PD — Planned duration
- Baseline duration from start to planned finish. Periods; use a positive value.
- e.g. 12
- AT — Actual time
- Time elapsed at the status date. Periods; must be greater than 0 for SPI(t).
- e.g. 8
- EV — Earned Value
- Budgeted value of the work actually complete. Same currency as BAC; zero is valid.
- e.g. 120000
Results
Earned time
- Earned Schedule (ES)
- The baseline time equivalent of the EV entered.
- Schedule Variance (SV(t))
- The time difference at the status date. Negative means late.
- Schedule Performance Index (SPI(t))
- Time efficiency, with 1.00 as the plan line.
Forecasting completion
- Independent Estimate at Completion (IEAC(t))
- A duration forecast under the same efficiency and linear-PV assumption; it is not a promise and it is not a calendar finish date.
How to use it
- Enter BAC and PD from the approved baseline, then enter EV and AT from the same status date.
- Read SV(t) for the time gap and SPI(t) for the direction and efficiency of travel. Check that the linear-PV assumption is reasonable for this project.
- Use IEAC(t) as a trend to test recovery options; reconcile it to the time-phased schedule before committing to a finish date.
Charts
- Earned time position
- The time the completed work earned against actual time and plan.
- SPI(t) time efficiency
- Earned schedule per period of actual time, crossed at 1.00.
01.3 — Time forecasting (SPI-based)
Planned duration ÷ SPI
Cost gets EAC; schedule gets this. Dividing the planned duration by the schedule performance index projects when the project will actually finish if the current pace continues. It is an approximation — SPI drifts back toward 1.0 late in a project as planned value tops out, so trust it early and mid-project and re-check often.
Forecast duration = Planned duration ÷ SPI
SPI = EV ÷ PV
Parameters
- Planned duration
- The baseline total duration, in any time unit — the forecast comes back in the same unit.
- e.g. 12
- EV — Earned Value
- Budgeted cost of the work actually completed to date.
- e.g. 45000
- PV — Planned Value
- Budgeted cost of the work scheduled to be done by now.
- e.g. 50000
Results
- SPI
- Pace versus plan — the engine of the forecast.
- Forecast duration
- Expected total duration if the current pace holds.
- Projected slip
- Forecast minus plan — the schedule overrun taking shape.
Charts
- Planned vs forecast duration
- Where the project lands if today’s pace holds — not a certainty, a trend.
02 — Budget & Burn Rate
The cash view of project health: how fast money is leaving, and how long the remaining budget lasts at that pace. Simpler than earned value — but it says nothing about what was delivered for the money, so read it next to % complete, never instead of it.
Budget & burn — PMI PMBOK Guide, Cost Management.
02.1 — Burn rate & runway
Spend pace · runway · budget used
Divide what you have spent by how long you have been spending it and you get the burn rate — the project’s cash velocity. Runway converts the remaining budget into time at that pace. Use any period unit (months, sprints); the runway comes back in the same unit.
Burn rate = Spent ÷ Periods elapsed
Runway = (Budget − Spent) ÷ Burn rate
Parameters
- Total budget
- Approved funds for the whole project.
- e.g. 120000
- Spent to date
- Actual cost so far — same as AC in earned value.
- e.g. 45000
- Periods elapsed
- How many months / sprints of spending produced that cost.
- e.g. 3
- Planned periods remaining (optional)
- How much longer the plan says the work will take — to test whether the money outlives the work.
- e.g. 6
Results
- Burn rate
- Average spend per period — the pace at which the budget is being consumed.
- Budget remaining
- Funds left before the budget is exhausted.
- Runway (periods)
- How many more periods the remaining budget lasts at the current burn rate.
- % of budget used
- Share of total funds already consumed.
Charts
- Runway vs plan
- Whether the remaining money outlasts the remaining work.
03 — Estimation
Turning uncertainty into a defensible number. For reference, typical estimate accuracy ranges: Rough Order of Magnitude −25% / +75%, Budget estimate −10% / +25%, Definitive estimate −5% / +10%.
Estimation — PMI Practice Standard for Project Estimating.
03.1 — Three-point estimate (PERT)
Triangular · Beta · σ · confidence ranges
Instead of a single guess, you estimate three scenarios and blend them. The PERT (beta) formula weights the most-likely case 4× because real outcomes cluster around it; the standard deviation then converts your optimism–pessimism spread into confidence ranges you can commit to. Works for durations and for costs alike. The 68 / 95 / 99.7% figures below are properties of the normal curve, while a single activity follows a skewed beta — read them as a good working approximation for one activity, and as genuinely accurate for the sum of several, which is where the roll-up below sends them.
Full analysis
Triangular = (O + M + P) ÷ 3
PERT (beta) = (O + 4M + P) ÷ 6
σ = (P − O) ÷ 6 Variance = σ²
Parameters
- O — Optimistic
- Best-case estimate: everything goes right. Roughly the 1-in-100 lucky outcome.
- e.g. 4
- M — Most Likely
- The realistic estimate you would give under normal conditions.
- e.g. 6
- P — Pessimistic
- Worst-case estimate: known risks materialise. Roughly the 1-in-100 unlucky outcome.
- e.g. 12
Results
- Triangular average
- Simple mean of the three points — use when you have no reason to trust M more.
- PERT (beta) estimate
- Weighted mean, 4× on Most Likely — the standard exam and planning answer.
- Standard deviation (σ)
- How spread out the outcome could be. A wide O–P gap means low confidence.
- Variance (σ²)
- σ squared. Variances (not σ) are what you add up along a path to get path-level uncertainty.
- 68% confidence (±1σ)
- Roughly two times in three, the real result lands inside this range.
- 95% confidence (±2σ)
- The range usually quoted when someone asks for a commitment.
- 99.7% confidence (±3σ)
- Near-certainty bounds — use for hard external deadlines.
Charts
- Three-point distribution
- The shape of the estimate, the PERT expected value, and the 68% band around it.
03.2 — Path uncertainty roll-up
σ(path) = √(Σ σ²)
Uncertainties don’t add — variances do. To get the uncertainty of a whole path (or project), square each activity’s σ, add them, and take the square root. The roll-up is always smaller than the simple sum of σ’s, which is why padding every task individually is wrong: the math already diversifies the risk. That diversification assumes the activities are INDEPENDENT. Correlated risks — one team, one supplier, one weather window — break the assumption, and the true path σ is then larger than this. It also covers a single path, not the merge bias where parallel paths converge.
σ(path) = √(σ₁² + σ₂² + … + σₙ²)
Parameters
- Activity σ values (comma-separated)
- The standard deviation of each activity on the path, from the three-point calculator above.
- e.g. 1.33, 0.5, 2
Results
- Path σ
- The combined uncertainty of the whole chain — use it for path-level confidence ranges.
- Naive sum of σ’s
- What you would get by simply adding the uncertainties — shown for contrast.
Charts
- Roll-up vs naive sum
- Why adding standard deviations overstates a path’s real uncertainty.
03.3 — Learning curve
T(n) = T₁ × n^(log rate ÷ log 2)
Every doubling of repetitions cuts the per-unit time by a fixed percentage: on an 80% curve, unit 2 takes 80% of unit 1’s time, unit 4 takes 80% of unit 2’s, and so on. Use it to estimate repetitive work — floors of a building, server migrations, test cycles — instead of multiplying the first unit’s time by the count. This is the unit (Crawford) model.
Time for unit n = T₁ × n^(log(rate ÷ 100) ÷ log 2)
rate is the learning rate as entered, in percent: 80 means 0.8
Parameters
- T₁ — first unit time (or cost)
- How long the first repetition took — the anchor of the curve.
- e.g. 100
- Learning rate (%)
- Per-doubling retention: 80 means each doubling takes 80% of the previous. Typical: 70–90%; 100 = no learning.
- e.g. 80
- Unit number (n)
- Which repetition you want the estimate for.
- e.g. 4
Results
- Time for unit n
- Predicted effort for that repetition.
- Improvement vs unit 1
- How much faster unit n is than the first attempt.
Charts
- Learning curve
- Per-unit time against a flat no-learning baseline, with the selected unit marked.
04 — Schedule & Critical Path
The critical path method finds which activities control the finish date. Early dates come from the forward pass, late dates from the backward pass; float is the gap between them.
Schedule — PMI Practice Standard for Scheduling.
04.1 — Float (slack)
Total float · free float · critical path test
Total float is how long an activity can slip without delaying the project finish. Free float is how long it can slip without delaying its immediate successor. Zero total float means the activity is on the critical path. Enter the dates from your forward/backward pass — either day numbers or durations, as long as they are consistent (this calculator uses the continuous convention where EF = ES + duration).
Full analysis
Total Float = LS − ES = LF − EF
Free Float = ES(successor) − EF
Parameters
- ES — Early Start
- The soonest the activity can start, from the forward pass.
- e.g. 5
- EF — Early Finish
- The soonest it can finish: ES + duration.
- e.g. 9
- LS — Late Start
- The latest it can start without delaying the project, from the backward pass.
- e.g. 8
- LF — Late Finish
- The latest it can finish without delaying the project.
- e.g. 12
- Successor ES (optional)
- Early start of the next activity — only needed for free float.
- e.g. 11
Results
- Total float
- Slip allowance before the project end date moves: LS − ES.
- Cross-check (LF − EF)
- Should equal LS − ES; a mismatch means a pass was computed inconsistently.
- Free float
- Slip allowance before the next activity is disturbed: successor ES − EF.
Charts
- Early vs late window
- How much room the activity has before it becomes critical.
05 — Schedule Compression
When the schedule must shrink there are only two levers: crashing buys time with money, fast-tracking buys it with risk. The cost slope tells you which activity sells the cheapest week.
Compression — PMI PMBOK Guide, Schedule Compression.
05.1 — Crash cost slope
(Crash cost − Normal cost) ÷ time saved
Most activities can be sped up — more people, overtime, premium suppliers — but only so far and at a price. The cost slope is the price of each time unit saved. To compress rationally: crash only critical-path activities, cheapest slope first, and stop when the slope costs more than the deadline is worth. Run this once per candidate activity and compare.
Cost slope = (Crash cost − Normal cost) ÷ (Normal duration − Crash duration)
Parameters
- Normal cost
- Cost of the activity at its normal, efficient pace.
- e.g. 10000
- Crash cost
- Cost at the fastest possible pace — overtime, extra staff, expediting fees included.
- e.g. 16000
- Normal duration
- Duration at the normal pace (any time unit).
- e.g. 10
- Crash duration
- The shortest duration physically achievable — beyond it, money buys nothing.
- e.g. 8
Results
- Cost slope
- Extra cost per time unit saved on this activity.
- Maximum time saved
- The most this activity can be shortened: normal minus crash duration.
- Full crash premium
- Total extra cost of buying all the available time.
Charts
- Normal vs crash
- The cost slope drawn as a line — its gradient is the price of each time unit saved.
06 — Resources & Team
Turning effort estimates into headcount, and checking whether the people you have are quietly over-committed.
Resources — PMI PMBOK Guide, Resource Management.
06.1 — Full-time equivalents (FTE)
Effort ÷ capacity
FTE converts a pile of estimated effort into how many full-time people the work actually needs within a given window. One FTE is one person fully allocated. Use productive hours per period, not contract hours — meetings, support and admin eat 15–30% before project work starts.
FTE = Effort hours ÷ (Productive hours per period × Periods)
Parameters
- Total effort (hours)
- Estimated person-hours of work to deliver in the window.
- e.g. 2080
- Productive hours / person / period
- Hours one person can really spend on this work each period — e.g. 130 of a 160-hour month after overhead.
- e.g. 130
- Periods in the window
- How many periods (months, sprints) the work is spread across.
- e.g. 4
Results
- FTE required
- Full-time people the work demands over the window.
- Headcount (rounded up)
- Whole people to staff if nobody can split across projects cleanly.
06.2 — Utilization
Allocated ÷ available
The share of a person’s available time already committed. Sustained utilization near 100% removes all slack: queues form, small surprises cascade, and cycle times explode (the queueing math behind this lives in Lean & Flow). Plan people like you plan servers — with headroom.
Utilization % = Allocated hours ÷ Available hours × 100
Parameters
- Allocated hours
- Hours of committed work in the period across all assignments.
- e.g. 150
- Available hours
- Hours the person actually has in the period.
- e.g. 160
Results
- Utilization
- Commitment level for the period.
- Uncommitted hours
- Hours left for the work nobody predicted.
Charts
- Commitment level
- Where utilization sits against the point delays start to amplify.
06.3 — Loaded labor cost
Rate × (1 + overhead)
A person’s cost to the project is never just their pay rate. The loaded (burdened) rate adds employer overhead — benefits, payroll taxes, equipment, facilities, licences — typically 25–50% on top. Budgets built on bare rates systematically understate cost and get discovered at the worst possible time.
Loaded cost = Hours × Rate × (1 + Overhead %)
Parameters
- Effort (hours)
- Person-hours of work being costed.
- e.g. 400
- Base rate (per hour)
- The bare pay or contract rate before burden.
- e.g. 60
- Overhead / burden (%)
- Employer add-ons as a percentage of the base rate — ask finance; 25–50% is typical for employees.
- e.g. 35
Results
- Base cost
- Hours × bare rate — the number that looks deceptively affordable.
- Loaded cost
- The true cost to the organisation, burden included.
- Loaded hourly rate
- The per-hour figure to use in every estimate.
07 — Communication
Why adding “just one more person” is never cheap: the number of one-to-one communication paths grows with the square of team size.
Communication — PMI PMBOK Guide, Communications Management.
07.1 — Communication channels
n(n−1) ÷ 2
Every pair of people on a project is a potential communication path that can carry — or garble — information. This count is used to justify communication plans, meeting structures and why large stakeholder groups need formal channels. Count everyone who communicates about the project, including yourself and the sponsor.
Channels = n × (n − 1) ÷ 2
Parameters
- n — People now
- Current number of people communicating on the project (team + stakeholders + you).
- e.g. 10
- People after change (optional)
- Headcount after adding or removing members — to see how many channels the change creates.
- e.g. 15
Results
- Channels now
- One-to-one paths that currently exist.
- Channels after change
- Paths at the new headcount.
- Channels added
- New paths the headcount change creates — the hidden coordination cost.
Charts
- Channel growth
- Why one more person on a large team costs more coordination than on a small one.
08 — Risk
Quantitative risk analysis puts money on uncertainty so risks can be compared, prioritised and reserved for.
Risk — PMI Risk Management in Portfolios, Programs, and Projects.
08.1 — Expected Monetary Value (EMV)
Probability × impact
EMV is the probability-weighted value of an uncertain event — what the risk is “worth” on average if you could run the project many times. Enter threats with a negative impact and opportunities with a positive one. Summing the EMV of every identified risk gives the contingency reserve; EMV is also the math behind decision-tree analysis.
Full analysis
EMV = Probability × Impact
Parameters
- Probability (%)
- Likelihood the risk event actually occurs, from qualitative analysis or data. 0–100.
- e.g. 30
- Impact
- Full monetary consequence if it occurs. Negative for threats (costs), positive for opportunities (gains).
- e.g. -50000
Results
- Expected Monetary Value
- The amount to carry in the contingency reserve for this single risk.
- Impact if it happens
- Reminder: EMV is an average — if the event fires you feel the full impact, not the EMV.
Charts
- EMV against full exposure
- The average outcome versus what actually happens if the event fires.
08.2 — Qualitative risk score
Probability × impact, on a 1–5 scale
Before risks are worth quantifying in money, they are ranked qualitatively: rate probability and impact on an agreed 1–5 scale and multiply. The product places each risk in the probability–impact matrix and decides how much attention it gets. The scales are ordinal — a 4 is not “twice” a 2 — so use the score to rank, not to budget.
Full analysis
Risk score = Probability (1–5) × Impact (1–5)
Parameters
- Probability rating (1–5)
- 1 = rare, 3 = possible, 5 = almost certain — per your organisation’s definitions.
- e.g. 4
- Impact rating (1–5)
- 1 = negligible, 3 = moderate, 5 = severe effect on objectives.
- e.g. 3
Results
- Risk score
- Position in the 25-cell probability–impact matrix.
Charts
- Probability–impact matrix
- Where this risk sits in the standard 5×5 grid.
08.3 — Contingency reserve roll-up
Σ EMV across the risk register
Sum the expected monetary value of every identified risk and you get the contingency reserve — the funded buffer for known-unknowns, owned by the project manager. Enter matching lists: one probability and one impact per risk, threats negative, opportunities positive. (Unknown-unknowns are covered separately by management reserve, which sits outside the baseline.)
Contingency reserve = − Σ (Probabilityᵢ × Impactᵢ)
Parameters
- Probabilities % (comma-separated)
- Likelihood of each risk, in register order — e.g. 30, 10, 50.
- e.g. 30, 10, 50
- Impacts (same order)
- Monetary consequence of each risk: threats negative, opportunities positive.
- e.g. -50000, -20000, 10000
Results
- Net EMV of the register
- Probability-weighted sum of all risks — usually negative when threats dominate.
- Suggested contingency reserve
- The buffer to add to the cost baseline (zero if net EMV is positive).
Charts
- Register contribution
- Which risks drive the reserve — each risk’s own EMV, side by side.
09 — Decision Analysis
Choosing under uncertainty: a decision tree multiplies what each choice costs by what it might return, so competing options can be compared on expected value instead of gut feel.
Decision — PMI PMBOK Guide, Decision Analysis.
09.1 — Decision tree — compare two options
EMV = −cost + p·payoff(success) + (1−p)·payoff(failure)
Each option is a branch: pay its cost, then chance decides between a success payoff and a failure payoff. The branch with the higher expected monetary value wins — on average. Classic uses: build vs buy, prototype vs commit, upgrade vs replace. Remember EMV is a long-run average; for one-shot, bet-the-company decisions, weigh the worst case too.
Full analysis
EMV(option) = − Cost
+ P(success) × Payoff(success)
+ (1 − P) × Payoff(failure)
Parameters
- Option A — cost
- Upfront cost of choosing branch A.
- e.g. 40000
- Option A — P(success) %
- Probability branch A succeeds.
- e.g. 60
- Option A — payoff if success
- Value delivered when A succeeds.
- e.g. 100000
- Option A — payoff if failure
- Value (often 0, sometimes negative) when A fails.
- e.g. 0
- Option B — cost
- Upfront cost of choosing branch B.
- e.g. 10000
- Option B — P(success) %
- Probability branch B succeeds.
- e.g. 30
- Option B — payoff if success
- Value delivered when B succeeds.
- e.g. 60000
- Option B — payoff if failure
- Value when B fails.
- e.g. 0
Results
- EMV — Option A
- Expected value of branch A after its cost.
- EMV — Option B
- Expected value of branch B after its cost.
- Better option
- The branch with the higher expected value, and by how much.
Charts
- Expected value comparison
- Which branch wins on average, and how wide a bet each one is.
10 — Quality & Six Sigma
Quality math answers two questions: how often does the process fail (DPMO, sigma level) and is it drifting out of control (control limits)?
Quality — ASQ Quality Resources and Six Sigma guidance.
10.1 — DPMO & sigma level
Defects per million opportunities
DPMO normalizes defect counts by how many chances there were to fail, so processes of different complexity can be compared fairly. The sigma level restates DPMO on the Six Sigma scale (with the conventional 1.5σ shift): 3σ ≈ 66,800 defects per million, 4σ ≈ 6,210, 6σ ≈ 3.4.
DPMO = Defects × 1,000,000 ÷ (Units × Opportunities per unit)
Sigma level ≈ 0.8406 + √(29.37 − 2.221 × ln DPMO)
Parameters
- Defects found
- Total defects observed in the sample.
- e.g. 25
- Units inspected
- How many items, transactions or deliverables were checked.
- e.g. 1000
- Opportunities per unit
- Distinct ways each unit could be defective — fields on a form, joints on an assembly.
- e.g. 4
Results
- DPMO
- Defects expected per million opportunities at this rate.
- Process yield
- Share of opportunities that pass defect-free.
- Sigma level
- The process capability on the Six Sigma scale, 1.5σ shift included.
Charts
- Sigma level
- Process performance on the Six Sigma scale.
10.2 — Control limits (±3σ)
UCL · LCL · warning zone
A control chart flags when a process leaves its normal noise band. The limits sit three standard deviations either side of the historical mean: a point outside them — or seven consecutive points on one side of the mean (the rule of seven) — signals the process is out of control and needs investigation, not tampering.
UCL = Mean + 3σ LCL = Mean − 3σ
Parameters
- Process mean
- The long-run average of the measurement, from historical data.
- e.g. 50
- Process σ
- Standard deviation of the measurement under normal conditions.
- e.g. 2
Results
- Upper control limit
- Mean + 3σ — the ceiling of normal variation.
- Lower control limit
- Mean − 3σ — the floor of normal variation.
- Warning zone (±2σ)
- Inner band where points are legal but worth watching.
Charts
- Control band
- The mean, the ±2σ warning zone, and the ±3σ control limits on one axis.
10.3 — Process capability (Cp / Cpk)
Can the process meet the spec?
Control limits describe what the process does; specification limits describe what the customer needs. Capability indices compare the two. Cp asks whether the spec window is wide enough for the process spread (ignoring centering); Cpk penalises a process that drifts off-centre. The common acceptance bar is Cpk ≥ 1.33.
Full analysis
Cp = (USL − LSL) ÷ 6σ
Cpk = min(USL − Mean, Mean − LSL) ÷ 3σ
Parameters
- USL — upper spec limit
- The highest value the customer or requirement accepts.
- e.g. 10
- LSL — lower spec limit
- The lowest acceptable value.
- e.g. 4
- Process mean
- Where the process actually centres, from measurement data.
- e.g. 6
- Process σ
- Standard deviation of the process output.
- e.g. 0.5
Results
- Cp — potential capability
- Spec width versus process spread, assuming perfect centering.
- Cpk — actual capability
- Capability including how far off-centre the process runs.
Charts
- Spec window vs process spread
- Whether the ±3σ process spread fits inside the customer’s spec limits, and how centred it is.
10.4 — Cost of Quality (CoQ)
Conformance vs failure spend
Everything quality costs, split into money spent on purpose and money lost to failure. Conformance costs are investments: prevention (training, standards, design reviews) and appraisal (testing, inspections, audits). Non-conformance costs are the bill for defects: internal failures (rework, scrap) and external ones (warranty, support, reputation). Mature organisations deliberately shift spend from the failure side to the prevention side.
Conformance = Prevention + Appraisal
Non-conformance = Internal failures + External failures
CoQ = Conformance + Non-conformance
Parameters
- Prevention costs
- Spent stopping defects from happening: training, standards, quality planning.
- e.g. 20000
- Appraisal costs
- Spent finding defects early: testing, inspection, audits.
- e.g. 30000
- Internal failure costs
- Defects caught before the customer: rework, scrap, retesting.
- e.g. 40000
- External failure costs
- Defects that reached the customer: warranty, incident response, lost business.
- e.g. 25000
Results
- Cost of conformance
- The deliberate investment in quality.
- Cost of non-conformance
- The price of failure, internal and external.
- Total cost of quality
- Everything quality costs, both sides combined.
- Failure share of CoQ
- What portion of quality spend is failure rather than investment.
Charts
- Conformance vs failure spend
- Where quality money goes — investment against the cost of failure.
11 — Project Selection & Finance
The business-case math used to choose between projects and to prove a project was worth doing. Rule of thumb across all of these: money later is worth less than money now.
Finance — PMI PMBOK Guide, Project Finance and Benefits.
11.1 — Return on Investment (ROI)
(Benefit − Cost) ÷ Cost
The simplest project-selection measure: how much you get back per unit invested, ignoring timing. Good for quick comparisons; misleading for long projects because it ignores when the money arrives — use NPV for that.
Full analysis
ROI % = (Benefit − Cost) ÷ Cost × 100
Parameters
- Total cost
- Everything invested in the project: build, licences, labour, run costs over the horizon you are measuring.
- e.g. 200000
- Total benefit
- Total value returned over the same horizon: revenue, savings, avoided costs.
- e.g. 260000
Results
- ROI
- Percentage return over the whole horizon (not per year).
- Net benefit
- Absolute value created: benefit minus cost.
11.2 — NPV · IRR · Payback
Discounted cash-flow appraisal
The rigorous way to value a project: every future cash flow is discounted back to today because money later is worth less than money now. NPV is the value created in today’s money; IRR is the discount rate at which the project merely breaks even; payback tells you how long capital is at risk. When choosing between projects, pick the higher NPV.
Full analysis
NPV = −Investment + Σ CFₜ ÷ (1 + r)ᵗ
IRR: the r where NPV = 0
Payback: periods until cumulative cash flow ≥ 0
Parameters
- Discount rate (%)
- Cost of capital or required return per period — the hurdle the project must beat.
- e.g. 10
- Initial investment
- Cash out at period 0, entered as a positive number.
- e.g. 1000
- Cash flows (comma-separated)
- Net cash in (or out, negative) for each following period, in order: period 1, 2, 3…
- e.g. 500, 500, 500
Results
- Net Present Value
- Value created in today’s money after paying back capital and the required return.
- Internal Rate of Return
- The project’s intrinsic return per period. Compare it to the discount rate. Reliable only for conventional flows — one outlay followed by inflows. If the signs change more than once, IRR can have several answers or none, and NPV is the measure to trust.
- Benefit–Cost Ratio
- Present value of the future net cash flows per unit invested — net, so a negative period nets off rather than counting as a benefit. Above 1 means benefits outweigh costs.
- Payback period
- Periods until the undiscounted cash recovers the investment — a measure of capital risk, not profitability.
Charts
- Cumulative cash flow
- Discounted against undiscounted — where the project actually breaks even.
11.3 — Present & Future Value
FV = PV(1 + r)ⁿ
The time-value-of-money primitive behind NPV. Future value answers “what will this be worth after n periods of compounding?”; present value answers the reverse: “what is a promised future amount worth today?”. Both outputs are computed from the single amount you enter.
FV = Amount × (1 + r)ⁿ
PV = Amount ÷ (1 + r)ⁿ
Parameters
- Amount
- The sum of money to move through time.
- e.g. 10000
- Rate per period (%)
- Interest or discount rate for each compounding period.
- e.g. 8
- Periods (n)
- Number of compounding periods — years if the rate is annual.
- e.g. 5
Results
- Future value
- What the amount grows to if invested today at the given rate.
- Present value
- What a payment of that amount, received n periods from now, is worth today.
- Doubling time (Rule of 72)
- 72 ÷ rate: the mental-math shortcut for how many periods money takes to double.
11.4 — Break-even point
Fixed costs ÷ contribution margin
How many units (or billable hours, or subscriptions) you must sell before the venture stops losing money. The denominator — price minus variable cost — is the contribution margin: what each unit contributes toward covering fixed costs.
Break-even units = Fixed costs ÷ (Price − Variable cost per unit)
Parameters
- Fixed costs
- Costs that exist regardless of volume: rent, salaries, licences, the project build itself.
- e.g. 50000
- Price per unit
- Revenue received for each unit sold.
- e.g. 25
- Variable cost per unit
- Cost incurred for each additional unit: materials, transaction fees, support.
- e.g. 15
Results
- Break-even units
- Volume at which total revenue equals total cost.
- Break-even revenue
- The revenue level at that volume.
- Contribution margin / unit
- Price − variable cost: what each sale contributes to fixed costs.
Charts
- Revenue vs cost
- Where the revenue line crosses total cost.
11.5 — Straight-line depreciation
(Cost − Salvage) ÷ Useful life
Spreads an asset’s cost evenly across its useful life — the depreciation method assumed in PMP exam questions and the simplest for business cases that must account for capital assets.
Annual depreciation = (Cost − Salvage value) ÷ Useful life
Parameters
- Purchase cost
- What the asset costs to acquire and put into service.
- e.g. 120000
- Salvage value
- Expected resale or scrap value at the end of its useful life.
- e.g. 20000
- Useful life (years)
- How many years the asset will be productive.
- e.g. 5
Results
- Depreciation per year
- The expense recognised each year of the asset’s life.
- Depreciation rate
- Share of the depreciable base expensed each year: 1 ÷ life.
11.6 — Weighted scoring model
Σ (weight × score)
The standard way to compare options against several criteria at once: weight each criterion by importance, score the option against each, and sum weight × score. Run it once per option and compare the totals. Its real value is political — the weights force stakeholders to argue about priorities before the decision, not after it.
Weighted score = Σ (weightᵢ × scoreᵢ) ÷ Σ weightᵢ
Parameters
- Criteria weights (comma-separated)
- Importance of each criterion, any scale — e.g. strategic fit 5, cost 3, risk 2.
- e.g. 5, 3, 2
- Option scores (same order)
- How this option rates on each criterion, on your scoring scale (say 1–10), in the same order as the weights.
- e.g. 8, 6, 9
Results
- Weighted score
- The option’s weighted average on your scoring scale — directly comparable across options.
- Raw weighted total
- The unnormalized Σ weight × score, as many textbooks present it.
Charts
- Weighted contribution
- Each criterion’s share of the total score — the weights, made visible.
12 — Procurement & Contracts
The math of incentive contracts (FPIF): buyer and seller share cost savings and overruns by an agreed ratio — until the point of total assumption, where the seller carries every extra dollar alone.
Procurement — PMI PMBOK Guide, Procurement Management.
12.1 — Point of Total Assumption (PTA)
Where the seller starts paying for overruns
In a Fixed-Price-Incentive-Fee contract, cost overruns are shared according to the buyer/seller ratio only up to the ceiling price. The PTA is the actual-cost level at which the buyer’s share of the overrun has consumed the room up to the ceiling; beyond it, every additional dollar of cost comes out of the seller’s fee. Sellers manage hard to stay below it.
PTA = (Ceiling price − Target price) ÷ Buyer share + Target cost
Parameters
- Ceiling price
- The maximum the buyer will ever pay, regardless of cost.
- e.g. 180000
- Target price
- Target cost + target fee: what both parties expect the buyer to pay.
- e.g. 165000
- Target cost
- The cost both parties negotiated as the expected outcome.
- e.g. 150000
- Buyer share (%)
- Buyer’s portion of the share ratio. An “80/20 split” means the buyer covers 80% of overruns — enter 80.
- e.g. 80
Results
- Point of Total Assumption
- The actual cost at which the seller assumes all further overrun.
- Overrun absorbed before PTA
- How much the cost can overrun target before the PTA is reached.
Charts
- Shared-risk band
- Target cost, the point of total assumption, and the ceiling on one cost axis.
12.2 — FPIF final fee & price
Settling an incentive contract
When the work is done, the incentive formula converts the cost outcome into the seller’s final fee: the seller keeps its share of any saving and gives up its share of any overrun. If a ceiling price is set, the buyer never pays more than it.
Final fee = Target fee + (Target cost − Actual cost) × Seller share
If the ceiling binds: Final fee = Ceiling price − Actual cost
Final price = min(Actual cost + Final fee, Ceiling price)
Parameters
- Target cost
- Negotiated expected cost of the work.
- e.g. 150000
- Target fee
- Profit the seller earns if actual cost exactly equals target cost.
- e.g. 15000
- Actual cost
- What the work really cost the seller.
- e.g. 140000
- Seller share (%)
- Seller’s portion of the ratio. In an 80/20 split, enter 20.
- e.g. 20
- Ceiling price (optional)
- Contract maximum — caps what the buyer pays.
- e.g. 180000
Results
- Final fee
- Seller’s profit after applying the incentive share. Once the ceiling binds, the fee erodes dollar for dollar with the overrun and can go negative.
- Final price (buyer pays)
- Actual cost plus final fee, capped at the ceiling if one is set.
Charts
- Final price vs actual cost
- The slope changes at the PTA and flattens at the ceiling — that bend is where seller risk changes.
12.3 — CPIF final fee & price
Cost-plus with a bounded incentive
In a Cost-Plus-Incentive-Fee contract the buyer reimburses all allowable costs, but the seller’s fee moves with performance: it grows when the seller beats the target cost and shrinks on overruns, always clamped between a negotiated minimum and maximum fee. Unlike FPIF there is no ceiling price — cost risk stays mostly with the buyer, which is why CPIF suits work too uncertain to fix-price.
Fee = Target fee + (Target cost − Actual cost) × Seller share
Final fee = clamp(Fee, Min fee, Max fee)
Final price = Actual cost + Final fee
Parameters
- Target cost
- Negotiated expected cost of the work.
- e.g. 100000
- Target fee
- Fee the seller earns if cost lands exactly on target.
- e.g. 10000
- Actual cost
- What the work really cost — fully reimbursed by the buyer.
- e.g. 90000
- Seller share (%)
- Seller’s portion of the share ratio. In an 80/20 split, enter 20.
- e.g. 20
- Minimum fee (optional)
- Fee floor — the least the seller can earn however badly cost overruns.
- e.g. 4000
- Maximum fee (optional)
- Fee ceiling — the most the seller can earn however well it performs.
- e.g. 15000
Results
- Final fee
- Incentive-adjusted fee, clamped to the min/max band if provided.
- Final price (buyer pays)
- Reimbursed actual cost plus the final fee — no ceiling in CPIF.
Charts
- Seller fee vs actual cost
- The fee moves with performance, then clamps flat at the negotiated floor and ceiling.
13 — Agile Forecasting
Empirical forecasting: measure what the team actually delivered, then project it forward. Velocity is a planning tool for the team — never a performance comparison between teams.
Agile — Scrum Guide (2020): scrumguides.org/scrum-guide.html
13.1 — Velocity & release forecast
Backlog ÷ velocity
Velocity is the average number of story points a team completes per sprint, measured from finished sprints only (yesterday’s weather). Dividing the remaining backlog by velocity gives the most honest forecast available: how many sprints of work remain at the current, demonstrated pace.
Full analysis
Velocity = Points completed ÷ Sprints completed
Sprints remaining = ⌈ Remaining backlog ÷ Velocity ⌉
Parameters
- Points completed
- Total story points fully done (meeting the Definition of Done) across the measured sprints.
- e.g. 120
- Sprints completed
- Number of finished sprints those points came from — use at least 3 for a stable average.
- e.g. 4
- Remaining backlog (points)
- Estimated points left in the release or project scope.
- e.g. 200
- Sprint length (weeks, optional)
- Length of one sprint — converts the forecast into calendar time.
- e.g. 2
Results
- Velocity
- Demonstrated delivery rate in points per sprint.
- Sprints remaining
- Whole sprints needed to clear the backlog at current velocity.
- Calendar time remaining
- Sprints remaining × sprint length.
Charts
- Backlog burndown forecast
- The remaining backlog burning down at the team’s demonstrated velocity.
13.2 — Sprint capacity
People × days × hours × focus
Capacity planning in hours, for sprint-level task commitment. Start from raw availability, then apply a focus factor — the share of the day genuinely available for sprint work after ceremonies, support duty, e-mail and context switching. Teams that skip the focus factor systematically over-commit. Use capacity for task hours; use velocity (above) for story points — they answer different questions.
Capacity = Members × Days × Hours per day × Focus factor
Parameters
- Team members
- People doing sprint work — count partial allocations as fractions (0.5 for half-time).
- e.g. 5
- Working days in sprint
- Sprint length minus holidays and planned leave.
- e.g. 9
- Hours per day
- Nominal working hours per person per day.
- e.g. 8
- Focus factor (%)
- Share of the day truly available for sprint work — 60–70% is realistic for most teams.
- e.g. 65
Results
- Raw hours
- Theoretical availability before reality intervenes.
- Plannable capacity (hours)
- What the team can actually commit to after the focus factor.
Charts
- Raw vs plannable capacity
- The focus factor is the gap — committing to raw hours is how sprints fail.
13.3 — Say/do ratio
Delivered ÷ committed
The simplest measure of forecast reliability: of what the team committed to at sprint planning, how much was actually delivered? Track it over several sprints. A team that consistently delivers what it says — even if it says less — is worth more to planning than a fast team nobody can predict.
Say/do % = Points delivered ÷ Points committed × 100
Parameters
- Points committed
- Story points the team signed up for at sprint planning.
- e.g. 34
- Points delivered
- Points fully done (per the Definition of Done) by sprint end.
- e.g. 29
Results
- Say/do ratio
- Forecast reliability for this sprint.
- Commitment gap (points)
- Delivered minus committed — negative means work rolled over.
Charts
- Forecast reliability
- Where the say/do ratio sits against the reliable band.
14 — Lean & Flow
Little’s Law is the physics of work in progress: the more you start, the slower everything finishes. It holds for any stable system — a kanban board, a help desk, a factory line.
Flow — Little (1961), “A Proof for L = λW”: doi.org/10.1287/opre.9.3.383
14.1 — Little’s Law & flow efficiency
Cycle time = WIP ÷ throughput
Given any two of work-in-progress, throughput and cycle time, Little’s Law fixes the third. It is the mathematical case for WIP limits: with throughput unchanged, every extra item you start adds directly to how long everything takes. Flow efficiency then reveals how much of that cycle time is actual work versus waiting in queues.
Cycle time = WIP ÷ Throughput
Flow efficiency % = Active work time ÷ Cycle time × 100
Parameters
- WIP — work in progress
- Items currently started and unfinished on the board.
- e.g. 12
- Throughput (items / period)
- Items finished per period — pick days or weeks and stay consistent.
- e.g. 3
- Active work per item (optional)
- Hands-on time an item actually receives, in the same period units — for flow efficiency.
- e.g. 0.5
Results
- Average cycle time
- How long a newly started item takes to finish, in your chosen periods.
- Flow efficiency
- Share of the cycle time that is real work rather than waiting.
Charts
- WIP vs cycle time
- The linear relationship behind WIP limits — at fixed throughput, cycle time tracks WIP directly.