Stream of cash flows: a series of cash flows lasting several periods. Can be
represented on a timeline: important first step in organizing and then solving a
financial problem.
The three rules of Time Travel:
- Comparing and combining values: It is only possible to compare or
combine values at the same point in time, because a dollar today and a
dollar in one year are not equivalent.
- Moving Cash Flows Forward in Time: compounding = our second rule
stipulates that to move a cash flow forward in time, you must compound
it. Compound interest: the effect of earning “interest on interest”.
Future Value of a Cash Flow: FVn = C x (1 + r)n
- Moving Cash Flows Back in Time: Discounting = the process of moving a
value or cash flow backward in time – finding the equivalent value of today
of a future cash flow.
Present value of a Cash Flow: PV = C / (1 + r) n
N
Present Value of a Cash Flow Stream: PV = ∑ PV (C n )
n=0
Future Value of a Cash Flow stream with a Present Value of PV: FV n = PV x (1 +
r)n
Aim: compare the costs and benefits of a project to evaluate a long-term
investment decision.
NPV = PV(benefits) – PV(costs)
NPV = PV(benefits – costs) present value of cash flows of the opportunity
Perpetuity: a stream of equal cash flows occurring at regular intervals and last
forever. (eg british government bond: consol).
The first cash flow occurs at the end of the first period = payment in arrears.
∞
C
PV = ∑( n
n =1 1+r )
When investing, we withdraw the interest we have earned, C = r x P, leaving the
principal P.
Present Value of a Perpetuity: PV (C in perpetuity) = C/ r
Annuity: a stream of N equal cash flows paid at regular intervals. ≠ w perpetuity
is that it ends.
Pinitial investment = PV (annuity of C for N periods) + PV ( P in period N)
PV (annuity of C for N periods) = P – PV (P in period N)
−P
PV (annuity of C for N periods) = P
( 1+ r )N
, Present Value of an Annuity: PV (annuity of C for N periods with the interest rate
−1
r) = C x (1/ r) (1 ¿
( 1+ r )N
Future Value of Annuity: FV (annuity) = C x (1/r) ((1 + r)N – 1)
Growing Perpetuity: a stream of cash flows occurring at regular intervals and
grow at a constant rate forever. The first payment doesn’t include growth.
∞
C ( 1+ g )n−1
PV = ∑ n
n =1 ( 1+r )
Present Value of a Growing Perpetuity: PV(growing perpetuity) = C / (r – g)
Growing annuity: a stream of N growing cash flows, paid at regular intervals. It is
a growing perpetuity that eventually comes to an end. The fist cash flow still
arrives at the end of the first period and the first cash flow does not grow.
1 1+ g N
Present Value of a Growing Annuity: PV = C¿ (1− )
r−g 1+r
PMT present value of annuity + FVpresent value of final payment + PV initial amount =0
Everything about annual cash flow streams applies to monthly cash flows
streams as long as the interest rate is specified as a monthly rate, the number of
periods is expressed in months.
Loan payment problem: to solve it, refer the load principal as the present value.
Then just has to inverse the annuity formula.
P
Loan or Annuity Payment: C = ∗(1− 1 )
1
r ( 1+ r )N
Internal rate of return (IRR) = the interest rate setting the net present value of
cash flow to 0
IRR with 2 cash flows = (FV / P)1/N – 1 compound annual growth rate
(CAGR)
IRR of growing perpetuity = (C/P) + g
Chap 5: Interest rates
Interest rates are often stated as effective annual rate (EAR): indicates the actual
amount being earned at the end of one year.
Adjusting the Discount Rate to Different Time periods: changing the power of the
interest rate (1 + r)
General Equation for Discount Rate Period Conversion: Equivalent n-Period
Discount Rate = (1+r)n –1
Annual Percentage Rate (APR) indicates the amount of simple interest earned in
one year, without the effect of compounding.
A way of quoting a monthly interest rate, rather than an annual one.
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller apollinecroc. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $4.42. You're not tied to anything after your purchase.