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Present Value: Definition and Calculation Future Value: Definition and Calculation Relationship between Present Value and Future Value
Net Present Value (NPV): Definition, Calculation, and Decision Rule Applications of Present Value and Future Value in Financial Decisions


Time Value of Money: Present and Future Value



Time Value of Money: Present and Future Value

Present Value (PV): Definition and Calculation

Definition

The concept of Present Value (PV) is fundamental to finance and investment. It represents the current worth of a sum of money that is to be received or paid in the future, or the current worth of a series of future cash flows. In simpler terms, it answers the question: "Given a specific rate of return, how much money must I invest today to have a certain amount at a future date?" or conversely, "What is the value today of an amount I expect to receive at some point in the future?".

The foundation of Present Value is the principle of the Time Value of Money (TVM). This principle asserts that a sum of money available today is worth more than the identical sum received at a future date. This is because money possessed today can be invested or utilized to earn interest or generate returns, thereby increasing its value over time. Consequently, money received in the future is worth less than the same amount received today. To find its equivalent value in the present, future money is 'discounted' back to the present using an appropriate rate of return, also known as the discount rate.

The process of calculating the present value is known as discounting. The rate used in this calculation is typically the required rate of return, cost of capital, or an interest rate that could be earned on an alternative investment of similar risk.

Calculation Formula and Derivation

The formula for calculating Present Value is derived directly from the formula for Future Value under compound interest. Recall the compound interest formula for the accumulated amount (which is the Future Value) after $n$ periods with a periodic interest rate $i$:

$FV = PV(1 + i)^n$

Where:

Our goal is to find the formula for $PV$. We can rearrange the Future Value formula to solve for $PV$ by dividing both sides by $(1 + i)^n$:

$\frac{FV}{(1 + i)^n} = \frac{PV(1 + i)^n}{(1 + i)^n}$

This simplifies to the formula for Present Value:

$\mathbf{PV = \frac{FV}{(1 + i)^n}}$

Using properties of exponents, we can also write this formula using a negative exponent:

$\mathbf{PV = FV(1 + i)^{-n}}$

The term $\frac{1}{(1+i)^n}$ or $(1+i)^{-n}$ is crucial in PV calculations. It is called the discount factor or present value factor. It represents the present value of $\textsf{₹}\$ 1$ (or any unit currency) to be received after $n$ periods, discounted at a rate of $i$ per period. Multiplying a future value by this discount factor gives its present value.

Key Factors Affecting Present Value

Based on the formula $PV = FV(1 + i)^{-n}$, we can see how changes in the other variables affect the Present Value:

Worked Examples

Example 1. What is the present value of $\textsf{₹}\$ 15,000$ to be received 4 years from now, if the discount rate is 9% per annum compounded annually?

Answer:

Given:

  • Future Value (FV) = $\textsf{₹}\$ 15,000$
  • Time (t) = 4 years
  • Annual Discount Rate (R) = 9%. Since compounded annually, the periodic rate $i = R/100 = 0.09$.
  • Compounding: Annually, $m=1$. Total periods $n = m \times t = 1 \times 4 = 4$.

To Find:

  • Present Value (PV).

Formula:

$PV = \frac{FV}{(1 + i)^n}$

Solution:

Substitute the given values into the formula:

$PV = \frac{15000}{(1 + 0.09)^4}$

$PV = \frac{15000}{(1.09)^4}$

Calculate $(1.09)^4$. Using a calculator:

$(1.09)^2 = 1.1881$

$(1.09)^4 = (1.09^2)^2 = (1.1881)^2 \approx 1.411581$

So,

$PV = \frac{15000}{1.411581}$

Performing the division:

$PV \approx 10626.37$

Rounding to two decimal places, the present value is approximately $\textsf{₹}\$ 10,626.37$. This means that $\textsf{₹}\$ 10,626.37$ invested today at an annual compound interest rate of 9% would grow to approximately $\textsf{₹}\$ 15,000$ in 4 years.


Example 2. Find the present value of $\textsf{₹}\$ 5,000$ due in 3 years if the interest rate is 8% p.a. compounded quarterly.

Answer:

Given:

  • Future Value (FV) = $\textsf{₹}\$ 5,000$
  • Time (t) = 3 years
  • Nominal annual rate (R) = 8%. Convert to decimal: $r = \frac{8}{100} = 0.08$.
  • Compounding frequency: Quarterly, so $m=4$.

To Find:

  • Present Value (PV).

Calculate Periodic Discount Rate (i) and Total Number of Periods (n):

Periodic rate $i = \frac{r}{m} = \frac{0.08}{4} = 0.02$. (This is the discount rate per quarter).

Total number of periods $n = m \times t = 4 \times 3 = 12$. (There are 12 quarters in 3 years).

Formula:

$PV = \frac{FV}{(1 + i)^n}$

Solution:

Substitute the calculated values of FV, i, and n into the formula:

$PV = \frac{5000}{(1 + 0.02)^{12}} = \frac{5000}{(1.02)^{12}}$

Calculate $(1.02)^{12}$. Using a calculator (or financial tables):

$(1.02)^{12} \approx 1.26824179

So,

$PV = \frac{5000}{1.26824179}$

Performing the division:

$PV \approx 3942.57$

Rounding to two decimal places, the present value is approximately $\textsf{₹}\$ 3,942.57$.

Summary for Competitive Exams

Present Value (PV): The current worth of a future sum of money. Reflects Time Value of Money (TVM).

Concept: Discounting future cash flows back to the present using a discount rate.

Formula: $\mathbf{PV = \frac{FV}{(1 + i)^n} = FV(1 + i)^{-n}}$

  • PV: Present Value
  • FV: Future Value
  • i: Periodic discount rate (decimal, $r/m$)
  • n: Total number of periods ($mt$)

Discount Factor: $(1 + i)^{-n}$. Represents the value today of 1 unit of currency received in $n$ periods.

Factors: PV increases with FV, decreases with higher $i$, and decreases with longer $n$.


Time Value of Money: Future Value (FV): Definition and Calculation

Definition

The Future Value (FV) is the value of an investment or a sum of money at a specified point in time in the future, assuming a certain rate of return or growth (interest rate). It addresses the question: "If I invest a certain amount of money today at a given interest rate, how much will it be worth after a specific number of periods?" or "What will be the value of my current savings after some years?"

Future Value calculations are used to project the growth of money due to the application of interest, particularly compound interest. This process of calculating the future value is also known as accumulation, as it shows how the initial principal accumulates interest over time.

The concept of Future Value is a direct application of the Time Value of Money (TVM), demonstrating that money grows when invested or lent at a positive interest rate.

Calculation Formula

The formula for Future Value (FV) is the standard compound interest formula for the accumulated amount. If you have a Present Value (PV) invested today, its Future Value after $n$ periods at a periodic interest rate $i$ is given by:

$\mathbf{FV = PV(1 + i)^n}$

Where:

If the nominal annual rate is $r$ compounded $m$ times per year over $t$ years, the formula can be written more explicitly as:

$\mathbf{FV = PV\left(1 + \frac{r}{m}\right)^{mt}}$

The term $(1+i)^n$ or $(1 + r/m)^{mt}$ is called the future value factor or accumulation factor. It represents the amount to which $\textsf{₹}\$ 1$ (or $1) invested today will grow after $n$ periods at an interest rate of $i$ per period. Multiplying the Present Value by this factor gives its Future Value.

Key Factors Affecting Future Value

Based on the formula $FV = PV(1 + i)^n$, the Future Value is influenced by:

Worked Examples

Example 1. If you deposit $\textsf{₹}\$ 35,000$ today in an account earning 8% per annum compounded annually, what will be the amount in the account after 5 years?

Answer:

Given:

  • Present Value (PV) = $\textsf{₹}\$ 35,000$
  • Time (t) = 5 years
  • Annual Rate (R) = 8%. Convert to decimal: $r = \frac{8}{100} = 0.08$.
  • Compounding: Annually, so $m=1$.

To Find:

  • Future Value (FV) after 5 years.

Calculate Periodic Rate (i) and Total Number of Periods (n):

Periodic rate $i = r/m = 0.08/1 = 0.08$.

Total number of periods $n = m \times t = 1 \times 5 = 5$.

Formula:

$FV = PV(1 + i)^n$

Solution:

Substitute the given values into the formula:

$FV = 35000 (1 + 0.08)^5$

$FV = 35000 (1.08)^5$

Calculate $(1.08)^5$. Using a calculator (or financial tables):

$(1.08)^5 \approx 1.469328$

So,

$FV = 35000 \times 1.469328$

Performing the multiplication:

$FV \approx 51426.48$

Rounding to two decimal places, the amount in the account after 5 years will be approximately $\textsf{₹}\$ 51,426.48$.


Example 2. Calculate the future value of $\textsf{₹}\$ 10,000$ invested for 3 years at 6% per annum compounded quarterly.

Answer:

Given:

  • Present Value (PV) = $\textsf{₹}\$ 10,000$
  • Time (t) = 3 years
  • Nominal annual rate (R) = 6%. Convert to decimal: $r = \frac{6}{100} = 0.06$.
  • Compounding frequency: Quarterly, so $m=4$.

To Find:

  • Future Value (FV) after 3 years.

Calculate Periodic Rate (i) and Total Number of Periods (n):

Periodic rate $i = \frac{r}{m} = \frac{0.06}{4} = 0.015$. (This is the interest rate per quarter).

Total number of periods $n = m \times t = 4 \times 3 = 12$. (There are 12 quarters in 3 years).

Formula:

$FV = PV(1 + i)^n$

Solution:

Substitute the given values into the formula:

$FV = 10000 (1 + 0.015)^{12}$

$FV = 10000 (1.015)^{12}$

Calculate $(1.015)^{12}$. Using a calculator (or financial tables):

$(1.015)^{12} \approx 1.19561817

So,

$FV = 10000 \times 1.19561817$

$FV \approx 11956.1817$

Rounding to two decimal places, the future value is approximately $\textsf{₹}\$ 11,956.18$.

Summary for Competitive Exams

Future Value (FV): The value of a current sum of money at a future date, assuming growth at a specific interest rate.

Concept: Accumulation of present value over time due to compounding.

Formula: $\mathbf{FV = PV(1 + i)^n = PV\left(1 + \frac{r}{m}\right)^{mt}}$

  • FV: Future Value
  • PV: Present Value
  • i: Periodic interest rate (decimal, $r/m$)
  • n: Total number of periods ($mt$)
  • r: Nominal annual rate (decimal)
  • m: Compounding frequency per year
  • t: Time in years

Accumulation Factor: $(1 + i)^n$ or $(1 + r/m)^{mt}$. Represents the future value of 1 unit of currency invested for $n$ periods.

Factors: FV increases with PV, higher $i$ (or $r$), and longer $n$ (or $t$ & $m$).


Time Value of Money: Relationship between Present Value and Future Value

Inverse Operations: Discounting and Accumulation

Present Value (PV) and Future Value (FV) are two sides of the same coin within the concept of the Time Value of Money. They represent the value of the same underlying sum of money but at different points in time, connected by the passage of time and the effect of the interest rate (or discount rate).

Accumulation moves money forward in time, while discounting moves money backward in time. They are perfectly symmetrical and are inverse operations.

The Core Relationship

The fundamental link between PV and FV is captured in the compound interest formula. Regardless of whether you are calculating FV from PV or PV from FV, the underlying relationship is the same:

$\mathbf{FV = PV(1 + i)^n}$

This equation shows that Future Value is the Present Value multiplied by the accumulation factor $(1+i)^n$.

Equivalently, rearranging this formula shows that Present Value is the Future Value divided by the accumulation factor, or multiplied by the discount factor:

$\mathbf{PV = \frac{FV}{(1 + i)^n} = FV(1 + i)^{-n}}$

These formulas mean that if you know any three of the four variables (PV, FV, periodic rate $i$, total periods $n$), you can always calculate the fourth.

Key Insights from the Relationship

Understanding the dynamic relationship between Present Value and Future Value is essential for evaluating investment opportunities, calculating loan repayments, valuing assets, and making any financial decision that involves cash flows occurring at different points in time. It allows financial analysts and individuals to compare the value of money consistently across time.

Summary for Competitive Exams

Core Principle: Time Value of Money (TVM) - Money today is worth more than money tomorrow.

Accumulation: Moving money FORWARD in time (PV to FV). Uses interest rate.

Discounting: Moving money BACKWARD in time (FV to PV). Uses discount rate.

Formula Linking PV and FV: $\mathbf{FV = PV(1 + i)^n}$ OR $\mathbf{PV = FV(1 + i)^{-n}}$

  • PV: Present Value
  • FV: Future Value
  • i: Periodic rate (decimal)
  • n: Total periods

Accumulation Factor: $(1+i)^n$. $FV = PV \times \text{Accumulation Factor}$.

Discount Factor: $(1+i)^{-n} = \frac{1}{(1+i)^n}$. $PV = FV \times \text{Discount Factor}$.

Relationship: PV < FV for $i>0, n>0$. Difference is Compound Interest.

Key Use: Comparing cash flows at different times, fundamental to all financial calculations.



Time Value of Money: Net Present Value (NPV): Definition, Calculation, and Decision Rule

Definition

The Net Present Value (NPV) is a sophisticated capital budgeting technique used to evaluate the profitability of an investment or project. It determines the value of all future cash flows, both positive (inflows) and negative (outflows), generated by a project, discounted back to their present value, and then subtracts the initial investment cost.

In essence, NPV measures the "net" benefit or wealth created (or lost) by undertaking a project today, considering that money has a time value. A positive NPV indicates that the project is expected to generate cash flows whose present value is greater than the initial cost, thereby adding value to the firm or investor in today's terms. A negative NPV suggests the project is expected to result in a loss of value in present terms.

The discount rate used in the NPV calculation is typically the required rate of return, cost of capital, or the opportunity cost of capital – the return that could be earned on an investment of similar risk elsewhere.

Calculation Formula

To calculate the Net Present Value (NPV), we need to identify all the cash flows associated with the project and the appropriate discount rate. The cash flows typically occur at different points in time.

Let:

The formula for NPV is the sum of the present values of all future cash flows, minus the present value of the initial investment (which is already at present value):

$\mathbf{NPV = \frac{C_1}{(1+i)^1} + \frac{C_2}{(1+i)^2} + \dots + \frac{C_n}{(1+i)^n} - C_0}$

Using the summation notation, this formula can be written more compactly:

$\mathbf{NPV = \sum_{t=1}^{n} \frac{C_t}{(1+i)^t} - C_0}$

... (1)

Alternatively, if we consider $C_0$ as the cash flow at time $t=0$ (which is negative), the formula can be written as the sum of the present values of all cash flows, starting from $t=0$:

$NPV = \frac{C_0}{(1+i)^0} + \frac{C_1}{(1+i)^1} + \frac{C_2}{(1+i)^2} + \dots + \frac{C_n}{(1+i)^n}$

Since $(1+i)^0 = 1$, this becomes:

$\mathbf{NPV = C_0 + \sum_{t=1}^{n} \frac{C_t}{(1+i)^t}}$ (where $C_0$ is a negative value)

... (2)

Both formulas are equivalent. Formula (1) explicitly shows the initial cost being subtracted, while formula (2) treats the initial cost as a negative cash flow at time zero and sums all present values.

Decision Rule for NPV

The Net Present Value method provides a clear rule for accepting or rejecting investment projects. This rule is based on the principle that businesses should accept projects that increase the wealth of their owners (or investors).

When choosing among mutually exclusive projects (projects where selecting one automatically means you cannot select the others), the project with the highest positive NPV is preferred, as it is expected to add the most value.

Worked Example

Example 1. A company is considering a project that requires an initial investment of $\textsf{₹}\$ 1,00,000$. The project is expected to generate cash inflows of $\textsf{₹}\$ 30,000$ at the end of Year 1, $\textsf{₹}\$ 40,000$ at the end of Year 2, $\textsf{₹}\$ 50,000$ at the end of Year 3, and $\textsf{₹}\$ 20,000$ at the end of Year 4. The company's required rate of return (discount rate) is 12% per annum. Calculate the Net Present Value (NPV) of the project and state whether the project should be accepted or rejected.

Answer:

Given:

  • Initial Investment ($C_0$) = $\textsf{₹}\$ 1,00,000$ (This is an outflow, so we treat it as -$\textsf{₹}\$ 1,00,000$ at $t=0$).
  • Cash Inflow Year 1 ($C_1$) = $\textsf{₹}\$ 30,000$ (at $t=1$).
  • Cash Inflow Year 2 ($C_2$) = $\textsf{₹}\$ 40,000$ (at $t=2$).
  • Cash Inflow Year 3 ($C_3$) = $\textsf{₹}\$ 50,000$ (at $t=3$).
  • Cash Inflow Year 4 ($C_4$) = $\textsf{₹}\$ 20,000$ (at $t=4$).
  • Required Rate of Return (Discount Rate, $i$) = 12% per annum = 0.12.

To Find:

  • Net Present Value (NPV).
  • Decision regarding project acceptance.

Formula:

We will use the formula $NPV = \sum_{t=1}^{n} \frac{C_t}{(1+i)^t} - C_0$.

In this case, $n=4$.

$NPV = \frac{C_1}{(1+i)^1} + \frac{C_2}{(1+i)^2} + \frac{C_3}{(1+i)^3} + \frac{C_4}{(1+i)^4} - C_0$

Solution: Calculate Present Value (PV) of each cash inflow

We need to calculate the discount factors $(1+i)^{-t}$ for each year $t$ at $i=0.12$ and multiply them by the respective cash flows $C_t$.

  • Year 1 (t=1): Discount factor $(1+0.12)^{-1} = (1.12)^{-1} = \frac{1}{1.12} \approx 0.892857$

    $PV(C_1) = 30000 \times 0.892857 \approx \textsf{₹}\$ 26785.71$

  • Year 2 (t=2): Discount factor $(1+0.12)^{-2} = (1.12)^{-2} = \frac{1}{(1.12)^2} = \frac{1}{1.2544} \approx 0.797194$

    $PV(C_2) = 40000 \times 0.797194 \approx \textsf{₹}\$ 31887.76$

  • Year 3 (t=3): Discount factor $(1+0.12)^{-3} = (1.12)^{-3} = \frac{1}{(1.12)^3} \approx \frac{1}{1.404928} \approx 0.711780$

    $PV(C_3) = 50000 \times 0.711780 \approx \textsf{₹}\$ 35589.00$

  • Year 4 (t=4): Discount factor $(1+0.12)^{-4} = (1.12)^{-4} \approx \frac{1}{1.573519} \approx 0.635518$

    $PV(C_4) = 20000 \times 0.635518 \approx \textsf{₹}\$ 12710.36$

Calculate Total Present Value of Inflows:

Sum of the present values of all future cash inflows:

Total PV of Inflows = $PV(C_1) + PV(C_2) + PV(C_3) + PV(C_4)$

Total PV of Inflows $\approx 26785.71 + 31887.76 + 35589.00 + 12710.36$

Let's perform the addition:

$\begin{array}{cccccccc} & 2 & 6 & 7 & 8 & 5 & . & 7 1 \\ & 3 & 1 & 8 & 8 & 7 & . & 7 6 \\ & 3 & 5 & 5 & 8 & 9 & . & 0 0 \\ + & 1 & 2 & 7 & 1 & 0 & . & 3 6 \\ \hline 1 & 0 & 6 & 9 & 7 2 & . & 8 3 \\ \hline \end{array}$

Total PV of Inflows $\approx \textsf{₹}\$ 1,06,972.83$

Calculate Net Present Value (NPV):

$NPV = (\text{Total PV of Inflows}) - (\text{Initial Investment})$

$NPV \approx \textsf{₹}\$ 1,06,972.83 - \textsf{₹}\$ 1,00,000$

Let's perform the subtraction:

$\begin{array}{cccccccc} & 1 & 0 & 6 & 9 & 7 2 & . & 8 3 \\ - & 1 & 0 & 0 & 0 & 0 0 & . & 0 0 \\ \hline & & 0 & 6 & 9 & 7 2 & . & 8 3 \\ \hline \end{array}$

$NPV \approx \textsf{₹}\$ 6,972.83$

Decision:

Since the calculated Net Present Value (NPV) is approximately $\textsf{₹}\$ 6,972.83$, which is a positive value ($NPV > 0$), the project is expected to generate a return greater than the required rate of return of 12%. This indicates that the project is financially attractive and is expected to increase the company's wealth.

Therefore, according to the NPV decision rule, the project should be accepted.

Summary for Competitive Exams

Net Present Value (NPV): Present value of future cash flows minus initial investment cost. Measures value creation in today's terms.

Formula: $\mathbf{NPV = \sum_{t=1}^{n} \frac{C_t}{(1+i)^t} - C_0}$ or $\mathbf{NPV = C_0 + \sum_{t=1}^{n} \frac{C_t}{(1+i)^t}}$ (with $C_0$ as negative outflow).

  • $C_t$: Net cash flow in period $t$.
  • $C_0$: Initial investment (outflow at $t=0$).
  • $i$: Discount rate per period (required return).
  • $n$: Project life in periods.

Decision Rule:

  • $\mathbf{NPV > 0: Accept}$ (Adds value)
  • $\mathbf{NPV < 0: Reject}$ (Destroys value)
  • $\mathbf{NPV = 0: Indifferent}$ (Meets required return)

For mutually exclusive projects, choose the one with the highest positive NPV.


Time Value of Money: Applications of Present Value and Future Value in Financial Decisions

Significance of PV and FV in Finance

The concepts of Present Value (PV) and Future Value (FV) are not merely academic exercises; they are the backbone of numerous financial calculations and decision-making processes for individuals, businesses, and governments. By providing a framework to compare the value of money across different points in time, they enable rational choices regarding investments, savings, borrowings, and asset valuation.

Key Applications

Here are some major applications of Present Value and Future Value concepts:

1. Investment Appraisal and Capital Budgeting

PV and FV are extensively used to evaluate the financial viability of potential investment projects (like buying new machinery, opening a new branch, etc.).

2. Valuation of Assets and Securities

The fair value of many financial assets and securities is determined by calculating the present value of the future cash flows they are expected to generate.

3. Loan Calculations and Management

PV and FV are fundamental to understanding and managing loans.

4. Personal Financial Planning (Savings and Retirement)

Individuals use PV and FV extensively for setting and achieving financial goals.

5. Comparing Cash Flows Occurring at Different Times

Perhaps the most basic application is simply bringing disparate cash flows to a common point in time for comparison. You cannot directly compare $\textsf{₹}\$ 1,000$ today with $\textsf{₹}\$ 1,100$ received a year from now without considering the time value of money. By calculating the FV of $\textsf{₹}\$ 1,000$ or the PV of $\textsf{₹}\$ 1,100$, you can make a direct, rational comparison based on a chosen interest rate.

6. Lease vs. Buy Decisions

Businesses often compare the cost of leasing an asset versus purchasing it. This involves calculating the present value of all future lease payments and comparing it to the purchase price (which is already a present value).

7. Insurance and Annuity Products

Pricing insurance policies and calculating payouts for annuities (a series of regular payments) heavily rely on calculating the present value of future payment streams and comparing them to the present value of premiums.

In conclusion, the ability to calculate and interpret Present Value and Future Value is an indispensable skill for making sound financial decisions, whether in personal finance, corporate finance, or investment management. These concepts provide the tools to account for the time value of money and compare financial opportunities on a consistent and rational basis.

Summary for Competitive Exams

PV and FV Applications: Used across finance to account for Time Value of Money.

Key Areas:

  • Investment Appraisal: Evaluating projects using NPV, IRR, PI (all based on PV). Accept positive NPV projects.
  • Valuation: Determining the fair price of assets (bonds, stocks, real estate) by discounting future cash flows (using PV formulas).
  • Loan Calculations: Calculating EMIs (PV of annuity formula), outstanding balances (PV of remaining payments).
  • Financial Planning: Setting savings goals (FV of current/future savings), retirement planning (FV of corpus, PV of future income needs).
  • Cash Flow Comparison: Bringing money from different times to a common point (usually PV) for comparison.
  • Lease vs. Buy: Comparing PV of lease payments to cost of buying.
  • Insurance/Annuities: Pricing products based on PV of future cash flows.

These applications highlight the practical importance of PV and FV in making informed financial decisions.