To-Complete Performance Index (TCPI) – Complete Guide for PMP Exam Success
To-Complete Performance Index (TCPI) is one of the most powerful Earned Value Management (EVM) forecasting metrics tested on the PMP exam. It tells a project manager how efficiently the remaining work must be performed in order to meet a specific financial target — either the original Budget at Completion (BAC) or a revised Estimate at Completion (EAC).
Why Is TCPI Important?
Project managers need to know more than just where a project stands today; they need to know what it will take to finish successfully. TCPI answers the critical question: "Given what we have spent so far, how efficient must we be on every remaining dollar of work to hit our budget (or revised estimate)?"
Key reasons TCPI matters:
• It provides a forward-looking efficiency requirement, unlike CPI which looks backward.
• It helps determine whether the remaining budget target is realistic or achievable.
• It supports decision-making about whether to continue with the original BAC or request a revised EAC.
• It is a key input for stakeholder communication — if the TCPI is unrealistically high, management can be informed early that the budget will likely be exceeded.
• It aligns with the PMBOK's emphasis on proactive monitoring and controlling of project finances and resources.
What Is TCPI?
TCPI is a ratio that represents the cost performance that must be achieved on the remaining work to meet a specified management goal (BAC or EAC).
In simple terms:
TCPI = (Work Remaining) / (Funds Remaining)
There are two formulas depending on the target:
1. TCPI based on BAC (original budget):
TCPI = (BAC − EV) / (BAC − AC)
This tells you how efficiently you must perform the remaining work to finish within the original budget.
2. TCPI based on EAC (revised estimate):
TCPI = (BAC − EV) / (EAC − AC)
This tells you how efficiently you must perform the remaining work to finish within a new revised estimate.
Where:
• BAC = Budget at Completion (total planned budget)
• EV = Earned Value (value of work actually completed)
• AC = Actual Cost (money actually spent so far)
• EAC = Estimate at Completion (revised total cost forecast)
How Does TCPI Work? (Interpretation)
The TCPI value is interpreted relative to 1.0:
• TCPI = 1.0 — You must perform at exactly the planned rate of efficiency for all remaining work. You are on track.
• TCPI > 1.0 — You must perform more efficiently than planned on all remaining work. The higher the number, the harder it is to achieve. A TCPI significantly above 1.0 (e.g., 1.4 or higher) is often considered unrealistic or unachievable.
• TCPI < 1.0 — You can perform less efficiently than planned and still meet your target. This means you have budget cushion remaining.
Worked Example:
A project has the following data:
• BAC = $100,000
• EV = $40,000
• AC = $50,000
• EAC = $125,000
TCPI (based on BAC):
TCPI = (100,000 − 40,000) / (100,000 − 50,000)
TCPI = 60,000 / 50,000 = 1.20
Interpretation: You must achieve a cost efficiency of 1.20 (i.e., get $1.20 of value for every $1.00 spent) on all remaining work to finish within the original $100,000 budget. This is 20% more efficient than planned — challenging but potentially achievable.
TCPI (based on EAC):
TCPI = (100,000 − 40,000) / (125,000 − 50,000)
TCPI = 60,000 / 75,000 = 0.80
Interpretation: If management approves the revised EAC of $125,000, you only need to achieve an efficiency of 0.80 on remaining work — meaning you can afford to be less efficient and still meet the new target.
Relationship Between TCPI and CPI:
• If CPI < 1.0 (over budget), then TCPI based on BAC will be > 1.0 — you need to improve efficiency to recover.
• If CPI > 1.0 (under budget), then TCPI based on BAC will be < 1.0 — you have room to spare.
• When using EAC in the TCPI formula, the TCPI value is typically closer to or below 1.0, because the EAC already accounts for the cost overrun.
• A useful cross-check: if TCPI (BAC) is much greater than the current CPI, the original budget is likely unachievable.
When to Use Each Formula:
• Use TCPI with BAC when the original budget is still considered valid and management has not approved a revised estimate.
• Use TCPI with EAC when a new estimate at completion has been approved and you want to know the efficiency needed to meet that revised target.
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Exam Tips: Answering Questions on To-Complete Performance Index (TCPI)
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Tip 1: Memorize Both Formulas
Know both TCPI formulas by heart. The exam may give you either BAC or EAC as the target. The numerator is always the same: (BAC − EV) which represents the work remaining. The denominator changes: (BAC − AC) for the BAC-based formula or (EAC − AC) for the EAC-based formula. Remember: the denominator represents the funds remaining for the respective target.
Tip 2: Read the Question Carefully for the Target
The exam question will specify (sometimes subtly) whether you are trying to meet the original budget or a revised estimate. Look for phrases like "finish within the original budget" (use BAC) vs. "meet the new estimate" or "revised forecast" (use EAC).
Tip 3: Understand Interpretation, Not Just Calculation
PMP questions may not always ask you to calculate TCPI. They may ask you to interpret a given TCPI value. Remember:
• TCPI > 1.0 = harder to achieve, must improve efficiency
• TCPI < 1.0 = easier to achieve, some budget flexibility
• TCPI = 1.0 = must perform exactly as planned
Tip 4: Know What an Unrealistic TCPI Means
If TCPI based on BAC is very high (e.g., 1.5 or above), the correct exam answer is often that the original budget is no longer achievable and the project should consider a revised EAC or formally request additional funding. The project manager should communicate this to stakeholders.
Tip 5: Relate TCPI to CPI
Some questions test your understanding of the relationship. If CPI is 0.8 and TCPI (BAC) is 1.3, this means the project is currently performing at 80% efficiency but needs to perform at 130% efficiency going forward — a significant gap that signals trouble.
Tip 6: Don't Confuse TCPI with CPI
CPI = EV / AC (measures past cost efficiency).
TCPI = (BAC − EV) / (BAC − AC) or (EAC − AC) (measures required future cost efficiency).
The exam may try to trick you by presenting options that swap these formulas.
Tip 7: Watch for Trick Questions with Negative Denominators
If AC exceeds BAC (i.e., BAC − AC is negative), the TCPI based on BAC becomes negative or undefined, meaning the original budget has already been fully spent with work remaining. In such a case, meeting the original budget is impossible.
Tip 8: Practice With Multiple Scenarios
Work through at least 5–10 practice problems with different combinations of BAC, EV, AC, and EAC values. Make sure you can calculate TCPI quickly and interpret results under time pressure.
Tip 9: Connect to the Bigger EVM Picture
TCPI is part of the broader Earned Value Management system. On the exam, it may appear alongside questions about SPI, CPI, EAC, ETC, and VAC. Understand how all these metrics work together to give a complete picture of project health. TCPI specifically fits into the Monitor and Control Project Work and Control Costs processes.
Tip 10: Remember the Conceptual Formula
If you forget the detailed formula during the exam, remember the conceptual version:
TCPI = Work Remaining / Funds Remaining
From this, you can reconstruct either formula:
• Work Remaining = BAC − EV
• Funds Remaining = BAC − AC (if targeting BAC) or EAC − AC (if targeting EAC)
Summary Table:
TCPI (BAC) = (BAC − EV) / (BAC − AC) → Efficiency needed to meet original budget
TCPI (EAC) = (BAC − EV) / (EAC − AC) → Efficiency needed to meet revised estimate
TCPI > 1.0 → Must be more efficient than planned (harder)
TCPI = 1.0 → Must perform exactly as planned
TCPI < 1.0 → Can be less efficient (easier, budget cushion exists)
Mastering TCPI gives you a significant advantage on the PMP exam, as it demonstrates your ability to not only track project performance but also to forecast and manage future performance — a core competency of effective project management.
