FM110 Flashcards
Discount Rate
A discount rate is the reward that investors demand for accepting delayed
rather than immediate gratification.
The discount rate is also called opportunity cost of capital because it is the
return foregone by investing in a capital project rather than investing in freelyavailable securities.
Simple Interest
Simple interest only pays interest on the original principal (principal is the term
used for the original amount of money invested).
Compound Interest
Compound interest pays interest not only on the original principal but also on
accumulated interest.
Stated Annual Interest Rate
The stated annual interest rate indicates the amount of simple interest earned in
a year and does not take into consideration interest earned on interest through
compounding. Therefore we do not discount with stated annual interest rates1
.
When accumulating or discounting cash flows to calculate present values or
future values we always use compound interest. Quoting the annual rate with
simple interest only is simply a convention.
e.g. 0.5% monthly = 0.005(12) = 0.06
Effective Annual Rate (EAR)
The effective annual rate (EAR) indicates the actual amount of interest that will
be earned at the end of the year after taking into consideration compounding
i.e. interest on interest.
(1+r)^n - 1
Converting a Stated Annual Interest Rate to an EAR
(1+EAR) = (1 + SAIR/n)^n
Future Value
If we are given a cash flow of C today it’s future value at time T is given by
FV = C(1+r)^t
where T is the number of time periods and r is the effective rate for the time
period and constant over time.
✓ Note the use of compound interest.
✓ Obviously the future value is larger if r or C or T is larger, ceteris paribus.
Present Value
Assume that you’re due to receive a payment of C at time T. The current cash
flow today that is equivalent to the future cash flow at time T is given by
PV = C/(1+r)^t
✓ Note the use of compound interest.
✓ Obviously the present value is smaller, if C is smaller, or r or T is larger, ceteris
paribus.
NPV Rule
Consider an investment project for which you have calculated the NPV.
✓ If the NPV is positive you should invest in the project.
✓ If the NPV is negative, you should turn down the investment opportunity.
The discount rate used in the NPV calculation should reflect the project’s
risk. More risky projects require a greater return and so you should use a
larger discount rate.
If you don’t know the cash flows associated with the project precisely, use the
expected value of each cash flow instead.
Why should I trust the NPV rule? Why is it optimal for individuals to invest in
projects with positive NPV and discard projects with negative NPV?
It turns out that NPV is optimal (under some assumptions) in the sense that
use of the rule leads to investors maximising their expected wealth.
This is true regardless of how patient or impatient an investor is, and thus
the rule can be used for all investors (they will all agree on which investments
to choose and which to discard).
Inflation Rate
The rate (usually annual) at which the level of prices in the economy increases.
Denote it by π.
Nominal Interest Rate
The rate at which the balance of a deposit grows in cash terms. Denote it by r .
Real Interest Rate
The rate at which the balance of a deposit grows in purchasing power terms.
Denote it by i.
The relationship between the real interest rate, the nominal interest rate and
the inflation rate is
(1+i) = (1+r)/(1+π)
Approximation for Real Interest Rate
r = i + π
Annuity with Growth
- The first cash flow occurs at the end of the 1st period and is denoted by C
- The cash flows must grow at a constant rate each period denoted by g
- The timing of the cash flows occur at constant intervals
- The discount rate is the effective rate for the time period in between cash flows and is constant over time and denoted by r
- There are n time petiods between cash flows where n is finite
- the PV valuation point is one period before the first cash flow
Annuity growth formula
PV = C((1- (1+g/1+r)^n) / r - g)
Annuity
- The first cash flow occurs at the end of the 1st period and is denoted by C
- The Cash flow C must be constant each period
- The timing of the cash flows occur at constant intervals
- The discount rate is the effective rate for the time period in between cash flows and is constant over time and is denoted by r
- There are n time periods between cash flows where n is finite
- The PV valuation point is one period before the first cash flow
-> The relevant discount rate to use in the annuity formula is the effective rate in between cash flows i.e. monthly effective rate
-> Used for mortgage problems mainly
Annuity Formula
PV = C((1 - 1/(1+r)^n )/ r)
Perpetuity with Growth
- The first cash flow occurs at the end of the 1st period and is denoted by C
- The cash flows must grow at a constant rate each period denoted by g
- The timing of the cash flows occur at constant intervals
- The discount rate is the effective rate for the period between cash flows and is constant over time and is denoted by r
- n the number of periods tends to infinity
- The PV valuation point is one period before the first cash flow
- The discount rate for the period in between cash flows has to be greater than the growth rate between cash flows i.e. r>g
Present Value of Perpetuity + Growth
C/r-g
Perpetuity
- The first cash flow occurs at the end of the 1st period and is denoted by C
- The cash flow C must be constant each period
- The timing of the cash flows occur at constant intervals
- The discount rate is the effective rate for the period in between cash flows and is constant over time and is denoted by r
- n the number of periods tends to infinity
- The PV valuation point is one period before the first cash flow
Perpetuity Formula
PVP = c/r
PVP, PVA, Annuity + Growth, Perpetuity + Growth use CFs where they occur at the end of the period, but what if CFs occur at the BEGINNING of the period? What two formulas can we use?
Annuity Due
Future Value Annuity