📊 1. Net Present Value (NPV)
✅ What is NPV?
Net Present Value is the difference between the present value of cash inflows and the present value of cash outflows over the life of a project.
📘 Formula:
NPV=∑Ct(1+r)t−C0NPV = sum frac{C_t}{(1 + r)^t} – C_0
Where:
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CtC_t = Cash inflow in year tt
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C0C_0 = Initial investment (cash outflow)
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rr = Discount rate (cost of capital)
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tt = Time period
💡 Decision Rule:
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NPV > 0 → Accept the project (adds value)
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NPV < 0 → Reject the project
📈 Advantages:
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Considers time value of money
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Uses all cash flows
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Directly relates to shareholder value
⚠️ Limitations:
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Requires accurate cash flow forecasts and discount rate
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Not suitable when comparing projects of unequal size/lifespan (use PI for that)
📉 2. Internal Rate of Return (IRR)
✅ What is IRR?
IRR is the discount rate that makes NPV = 0. It represents the project’s expected annual rate of return.
📘 Formula (solving for IRR numerically):
0=∑Ct(1+IRR)t−C00 = sum frac{C_t}{(1 + IRR)^t} – C_0
Decision Rule:
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IRR > cost of capital → Accept
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IRR < cost of capital → Reject
📈 Advantages:
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Easy to interpret as a percentage
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Useful for ranking multiple projects
⚠️ Limitations:
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May produce multiple IRRs with unconventional cash flows
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Can be misleading for mutually exclusive or non-standard projects
⏱️ 3. Payback Period and Discounted Payback Period
🔹 A. Payback Period
Time it takes for the project to recover its initial investment without discounting future cash flows.
📘 Formula:
Payback Period=Time when cumulative cash inflow = initial investmenttext{Payback Period} = text{Time when cumulative cash inflow = initial investment}
🔹 B. Discounted Payback Period
Same as Payback Period, but uses present value of cash flows.
💡 Decision Rule:
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Shorter payback → more attractive (used as a liquidity/risk measure)
📈 Advantages:
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Simple and quick
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Useful when cash flow timing is critical (e.g., for startups or risky ventures)
⚠️ Limitations:
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Ignores cash flows after payback
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Doesn’t consider time value of money (unless discounted)
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Not aligned with shareholder value maximization
📊 4. Profitability Index (PI)
✅ What is PI?
PI measures the value created per unit of investment. It’s the ratio of the present value of future cash inflows to the initial investment.
📘 Formula:
PI=PV of future cash inflowsInitial Investment=NPV+C0C0PI = frac{text{PV of future cash inflows}}{text{Initial Investment}} = frac{NPV + C_0}{C_0}
💡 Decision Rule:
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PI > 1.0 → Accept
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PI < 1.0 → Reject
📈 Advantages:
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Useful when capital is limited (e.g., ranking projects under a budget)
-
Considers time value and relative efficiency
⚠️ Limitations:
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Cannot always distinguish between projects of different scales (NPV is better for absolute value)
🧠 Summary Table: Key Financial Evaluation Metrics
| Metric | Key Feature | Accept Rule | Pros | Cons |
|---|---|---|---|---|
| NPV | Dollar value added | NPV > 0 | Considers all cash flows, TVM | Requires discount rate |
| IRR | Rate of return | IRR > cost of capital | Easy to compare | Multiple IRRs possible |
| Payback Period | Time to recover investment | Lower is better | Simple, useful for liquidity | Ignores later cash flows, TVM |
| Discounted Payback | Payback using PV of cash flows | Lower is better | More accurate than regular payback | Still ignores post-payback cash flows |
| Profitability Index | Value per dollar invested | PI > 1 | Good for capital rationing | Less useful for large-scale comparisons |
✅ Tools for Evaluation
| Tool | Usage |
|---|---|
| Excel NPV() | =NPV(rate, cash_flows) + initial_investment |
| Excel IRR() | =IRR(cash_flow_range) |
| NPV Sensitivity Tables | Vary discount rate or cash inflows |