FV - Future Value
PV - Present Value
R - Compouand annual return
n - Investment horizon
EAR - Effective Annual Rate
Pn - Price at the end of n
Pn-1 - Price at the end of n-1
FV = PV * (1+R)^n
PV = FV/ (1+R)^n
R = (FV/PV)^(1/n) - 1
n = ln(FV/PV)/ln(1+R)
If n is infinite
If n is infinite and Growing FV
Compounding occurs m times per year --> FV = PV(1+R/m)^(n*m)
Conitnuos Compounding - m is infinite --> FV = PV*e^(R*n), e = 2.71828
Compounding occurs m times per year --> PV(1+R/m)^(n*m) = PV(1+ EAR)^n --> EAR = (1+R/m)^(m) - 1
Conitnuos Compounding - m is infinitve --> PV*e^(R*n)= PV(1+ EAR)^n --> EAR = e^(R)- 1
Net return over n period --> Rn = (Pn - Pn-1)/Pn-1
Gross return over n period --> 1 + Rn = (Pn)/Pn-1
Multiple period returns
Net Return, Rn(2) = (Pn - Pn-2)/Pn-2 = (Pn/Pn-2) - 1
Relationship to 1 period returns
Net Return, Rn(2) = (Pn/Pn-2) - 1 = (Pn/Pn-1) * (Pn-1/Pn-2) - 1 = (1+Rn) * (1+Rn-1) - 1
Gross Return,1+Rn(2) = (1+Rn) * (1+Rn-1)
!!! 2 period gross return = the product of 2 1-period gross returns
Net Return, Rn(k) = (Pn / Pn-k) - 1
Gross Return,1+Rn(k) = (1+Rn) * (1+Rn-1) * (1+Rn-2) ....... * (1+Rn-k+1)
SA = % of Stock B, RA = return of Stock A
SB = % of Stock B, RB = return of Stock B
SA + SB = 100%
Rp = SA*RA + SB * RB
Dn = dividend received
Net Return, R = (Pn + Dn - Pn-1)/ Pn-1
Gross Return, 1 + R = (Pn + Dn)/ Pn-1
Ifn = Inflation over period n
Deflated price by using Inflation, Pr = P/Ifn
Return with Infaltion, Ri = (Pr - Prn-1) / Prn-1
= ( (P/Ifn) - (Pn-1/Ifn-1))/ (Pn-1/Ifn-1)
continuosly compounded return, r = ln(1+R) = ln(Pn/Pn-1)
given r, R = e^r - 1
r is alway smaller than R
says r = R/m, where m is infinite
e^r = e^(ln(1+R))
= e^(ln(Pn/Pn-1))
= Pn/Pn-1
Pn = Pn-1 * e^r
!!! see "Notes on natural log and exponential functions" sections for more details on natural log functions
Multiple period returns
r(2) =ln(Pn/Pn-2)
= ln(Pn/Pn-1 x Pn-1/Pn-2)
= ln(Pn/Pn-1) + ln(Pn-1/Pn-2)
= r period n + r period n -1
!!! cc returns are additive
Rp = SA*RA + SB * RB
rp = ln(1+Rp) = ln(1 + (SA*RA + SB * RB)) <> SA*rA + SB * rB --> portoflio cc returns are not additive
Return with Inflation
Ri = (Pn/Pn-1) * (Ifn-1/Ifn) - 1
1 + Ri = (Pn/Pn-1) * (Ifn-1/Ifn)
ri = ln(1 + Ri)
= ln( (Pn/Pn-1) * (Ifn-1/Ifn) )
= ln( (Pn/Pn-1)) + ln( (Ifn-1/Ifn) )
e = 2.7183
ln(e^x) = x, e^ln(x) = x
ln(x * y) = ln(x) + ln(y)
ln(x/y) = ln(x) - ln(y)
ln(x^y) = y * ln(x)
e^x * e^y = e^(x+y)
(e^x)^y = e^(x * y)
Created by Tan KW | Nov 25, 2024
Created by Tan KW | Nov 25, 2024
Created by Tan KW | Nov 25, 2024
sharemania
thanks for the sharing. useful indeed !
2013-04-08 08:43