CFP - Formulas Flashcards
Rp
Portfolio Return
Rm
Market or Benchmark Return
σp
standard deviation of portfolio returns (Variability)
σm
standard deviation of market returns
ρpm
Correlation of p to m
(ranges from -1 to +1)
R-Squared
Correlation Squared. AKA “Coefficient of Determination”
This number must be 80%. Otherwise risk-adjusted performance numbers are not valid.
Rf
Risk Free rate of return (90 day T-Bill)
βp
Portfolio Beta (systematic risk) (Volatility) = relative variability
Risk Premium of the Market
Rm – Rf
Market or Benchmark Return - Risk Free rate of return (90 day T-Bill)
Risk Premium of a portfolio
β(Rm – Rf)
Active Return
Rp – Rm
Portfolio Return - Market or Benchmark Return
“alpha” (be careful not to confuse this with Jensen’s alpha)
Active Risk
σ(Rp – Rm)
(Tracking Error (TE)) = standard deviation of active returns
Portfolio Beta
βp=ρpm×σp / σm
Portfolio Beta is the correlation of portfolio (p) to the market (m) times the standard deviation of p relative to (divided by) the market standard deviation. This is the risk which remains after diversification. Correlation (ρpm) must be high (0.85+) for Beta to be relevant
Portfolio required rate of return
Rp=Rf+(Rm–Rf)βp
The portfolio required rate of return (CAPM) is equal to the risk-free rate of return plus the risk premium of the market times the Beta (relative risk) of the portfolio.
The Sharpe Ratio
Sp=Rp−Rf / σp
=Risk Premium / Total Risk
The Sharpe Ratio measures return relative to total risk by dividing the return of the portfolio (above the risk free rate) by the total risk of the portfolio