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Lecture 8: Advanced Cash Flow Valuation

Introduction to Advanced Cash Flows

Building on Previous Knowledge: We learned about simple cash flows and annuities in Lecture 7. Now we explore more complex cash flow patterns used in real-world finance.

Five Types of Cash Flows:

  1. Simple Cash Flow: Single payment at one point in time
  2. Annuity: Constant payments over a fixed period
  3. Growing Annuity: Payments that grow at a constant rate
  4. Perpetuity: Constant payments forever
  5. Growing Perpetuity: Payments that grow forever

Key Insight: By combining these basic cash flow types, we can value almost any financial security or investment project.

Simple Analogy: Like building blocks - with these five basic types, we can construct complex financial structures.

Future Value of Annuities

Definition

Future Value of Annuity: The value at the end of the period of all regular payments plus accumulated interest.

Key Difference from Present Value:

  • Present Value: What are the payments worth today?
  • Future Value: What will the payments be worth at the end?

Example: Savings Account

Scenario: You deposit $2,000 at the end of each year for 3 years

  • Interest Rate: 8%
  • Question: How much will you have at the end of 3 years?

Step-by-Step Calculation:

  • Year 1: $2,000 deposited, earns interest for 2 years
  • Year 2: $2,000 deposited, earns interest for 1 year
  • Year 3: $2,000 deposited, no interest earned

Calculation:

  • Year 1: 2,000×(1.08)2=2,332.802{,}000 \times (1.08)^2 = 2{,}332.80
  • Year 2: 2,000×(1.08)1=2,160.002{,}000 \times (1.08)^1 = 2{,}160.00
  • Year 3: 2,000×(1.08)0=2,000.002{,}000 \times (1.08)^0 = 2{,}000.00
  • Total: 6,492.806{,}492.80

Future Value of Annuity

FVannuity=Payment×(1+r)n1r\text{FV}_{\text{annuity}} = \text{Payment} \times \frac{(1 + r)^n - 1}{r}

Where:

  • Payment = Regular payment amount
  • r = Interest rate per period
  • n = Number of periods

Using the Formula:

  • FV=2,000×(1.08)310.08\text{FV} = 2,000 \times \frac{(1.08)^3 - 1}{0.08}
  • FV=2,000×1.259710.08\text{FV} = 2,000 \times \frac{1.2597 - 1}{0.08}
  • FV=2,000×0.25970.08\text{FV} = 2,000 \times \frac{0.2597}{0.08}
  • FV=2,000×3.246\text{FV} = 2,000 \times 3.246
  • FV=6,492\text{FV} = 6,492

Growing Annuities

Definition

Growing Annuity: A series of payments that increase at a constant rate over a fixed period.

Real-World Examples:

  • Salary increases over time
  • Rent escalations
  • Dividend growth
  • Revenue growth projections

Present Value of Growing Annuity

PVgrowing annuity=Payment×1(1+g1+r)nrg\text{PV}_{\text{growing annuity}} = \text{Payment} \times \frac{1 - \left(\frac{1 + g}{1 + r}\right)^n}{r - g}

Where:

  • Payment = First payment amount
  • g = Growth rate
  • r = Discount rate
  • n = Number of periods

Important: r must be greater than g for the formula to work.

Practical Example: Gold Mine Valuation

Scenario: You own a gold mine for 20 years

  • Annual Production: 5,000 ounces
  • Current Gold Price: $300 per ounce
  • Price Growth: 3% per year
  • Required Return: 10%

Step 1: Calculate Initial Cash Flow

  • Year 0: 5,000×300=1,500,0005{,}000 \times 300 = 1{,}500{,}000

Step 2: Calculate Future Cash Flows

  • Year 1: 1,500,000×1.03=1,545,0001{,}500{,}000 \times 1.03 = 1{,}545{,}000
  • Year 2: 1,545,000×1.03=1,591,3501{,}545{,}000 \times 1.03 = 1{,}591{,}350
  • And so on...

Step 3: Calculate Present Value Using the growing annuity formula:

  • PV=1,545,000×1(1.031.10)200.100.03\text{PV} = 1,545,000 \times \frac{1 - \left(\frac{1.03}{1.10}\right)^{20}}{0.10 - 0.03}
  • PV=1,545,000×10.9367200.07\text{PV} = 1,545,000 \times \frac{1 - 0.9367^{20}}{0.07}
  • PV=1,545,000×10.45640.07\text{PV} = 1,545,000 \times \frac{1 - 0.4564}{0.07}
  • PV=1,545,000×0.54360.07\text{PV} = 1,545,000 \times \frac{0.5436}{0.07}
  • PV=1,545,000×7.766\text{PV} = 1,545,000 \times 7.766
  • PV=12,000,000\text{PV} = 12,000,000

Decision: This is the fair price of the mine. Paying more would result in negative NPV.

Perpetuities

Definition

Perpetuity: A series of constant payments that continue forever.

Historical Context: Used since the 17th-18th centuries by governments to finance wars and projects.

Modern Examples:

  • British Consol bonds (perpetual government bonds)
  • Preferred stock with fixed dividends
  • Some types of annuities

Present Value of Perpetuity

PVperpetuity=Paymentr\text{PV}_{\text{perpetuity}} = \frac{\text{Payment}}{r}

Where:

  • Payment = Constant payment amount
  • r = Required rate of return

Key Insight: The formula is surprisingly simple - just divide the payment by the interest rate.

Example: British Consol Bond

Scenario: British government bond paying £60 forever

  • Required Return: 9%
  • Question: What is the bond worth today?

Calculation:

  • PV=£600.09\text{PV} = \frac{\pounds 60}{0.09}
  • PV=£666.67\text{PV} = \pounds 666.67

Verification: If we calculate 200 years of payments, we get approximately the same result, proving that payments beyond 50-100 years contribute almost nothing to present value.

Growing Perpetuities

Definition

Growing Perpetuity: A series of payments that grow at a constant rate forever.

Why Important: This is the foundation of stock valuation models.

Present Value of Growing Perpetuity

PVgrowing perpetuity=Paymentrg\text{PV}_{\text{growing perpetuity}} = \frac{\text{Payment}}{r - g}

Where:

  • Payment = First payment amount
  • r = Required rate of return
  • g = Growth rate

Important: r must be greater than g for the formula to work.

Example: Growing Dividend Stock

Scenario: Stock with growing dividends

  • Current Dividend: $60
  • Growth Rate: 3%
  • Required Return: 9%

Calculation:

  • PV=600.090.03\text{PV} = \frac{60}{0.09 - 0.03}
  • PV=600.06\text{PV} = \frac{60}{0.06}
  • PV=1,000\text{PV} = 1,000

Comparison with Constant Perpetuity:

  • Constant perpetuity: 600.09=666.67\frac{60}{0.09} = 666.67
  • Growing perpetuity: 600.06=1,000\frac{60}{0.06} = 1{,}000
  • Difference: 333.33333.33 (50% higher value due to growth)

Stock Valuation Models

Dividend Discount Model (DDM)

Basic Idea: A stock's value equals the present value of all future dividends.

Why Dividends Matter:

  • Dividend Payments: Direct cash returns to shareholders
  • Capital Gains: Stock price appreciation based on expected future dividends
  • Key Insight: Everything comes back to dividends eventually

Constant Growth Model (Gordon Growth Model)

Formula:

Stock Price=D1rg\text{Stock Price} = \frac{D_1}{r - g}

Where:

  • D₁ = Next year's expected dividend
  • r = Required rate of return
  • g = Constant growth rate

Practical Example: Southwest Airlines (1992)

Data:

  • Last Dividend Paid: $2.73
  • Historical Growth Rate: 6%
  • Required Return: 12.23%

Step 1: Calculate Next Year's Dividend

  • D1=2.73×1.06=2.89D_1 = 2.73 \times 1.06 = 2.89

Step 2: Apply Gordon Growth Model

  • Stock Price=2.890.12230.06\text{Stock Price} = \frac{2.89}{0.1223 - 0.06}
  • Stock Price=2.890.0623\text{Stock Price} = \frac{2.89}{0.0623}
  • Stock Price=46.45\text{Stock Price} = 46.45

Result: According to the model, Southwest Airlines should trade at $46.45 per share.

Common Mistakes to Avoid

  1. Using Current Dividend Instead of Next Year's: Always use D₁, not D₀
  2. Growth Rate Assumptions: Be realistic about long-term growth rates
  3. Required Return: Must be greater than growth rate
  4. Dividend Timing: Understand when dividends are paid

Practical Examples

Example 1: Retirement Planning with Growing Annuities

Scenario: 30-year-old planning retirement

  • Annual Savings: $5,000 (grows 3% per year)
  • Time Horizon: 35 years
  • Expected Return: 8%

Analysis: Calculate future value of growing annuity to determine retirement fund size.

Example 2: Real Estate Investment

Scenario: Apartment building with growing rent

  • Current Annual Rent: $100,000
  • Rent Growth: 2% per year
  • Required Return: 10%
  • Holding Period: 20 years

Analysis: Use growing annuity formula to value the rental income stream.

Example 3: Company Valuation

Scenario: Tech startup with growing revenues

  • Current Revenue: $1 million
  • Growth Rate: 15% per year
  • Required Return: 20%
  • Question: What is the company worth?

Analysis: Apply growing perpetuity model (assuming company continues forever).

Example 4: Bond vs Stock Comparison

Scenario: Choosing between government bond and dividend stock

  • Bond: Pays $100 forever (perpetuity)
  • Stock: Pays $100 growing 2% forever (growing perpetuity)
  • Required Return: 8%

Analysis:

  • Bond Value: 1000.08=1,250\frac{100}{0.08} = 1,250
  • Stock Value: 1000.080.02=1,667\frac{100}{0.08 - 0.02} = 1,667
  • Decision: Stock is more valuable due to growth

Key Takeaways

  1. Five Cash Flow Types: Simple, annuity, growing annuity, perpetuity, growing perpetuity

  2. Future Value of Annuities: Value at the end of the period, calculated using compounding

  3. Growing Annuities: Payments that increase at a constant rate over time

  4. Perpetuities: Constant payments forever, valued using simple formula (Payment / r)

  5. Growing Perpetuities: Growing payments forever, foundation of stock valuation

  6. Stock Valuation: Gordon Growth Model uses growing perpetuity concept

  7. Key Formulas:

    • Future Value of Annuity: FV=Payment×(1+r)n1r\text{FV} = \text{Payment} \times \frac{(1 + r)^n - 1}{r}
    • Growing Annuity PV: PV=Payment×1(1+g1+r)nrg\text{PV} = \text{Payment} \times \frac{1 - \left(\frac{1 + g}{1 + r}\right)^n}{r - g}
    • Perpetuity PV: PV=Paymentr\text{PV} = \frac{\text{Payment}}{r}
    • Growing Perpetuity PV: PV=Paymentrg\text{PV} = \frac{\text{Payment}}{r - g}
    • Stock Price: Price=D1rg\text{Price} = \frac{D_1}{r - g}
  8. Important Rules:

    • r must be greater than g for growing formulas
    • Use D₁ (next year's dividend) for stock valuation
    • Present value of distant payments approaches zero
  9. Practical Applications: Retirement planning, real estate, company valuation, investment analysis

  10. Real-World Limitations: Models assume constant growth and required returns, which may not hold in practice