EquityPortfolioTrackingError.pptVIP

Equity Portfolio Tracking Error Raman Vardharaj Quantitative Portfolio Manager Guardian Life Insurance This presentation is based on the following unpublished paper: 揇eterminants of tracking error for equity portfolios?by Raman Vardharaj, Frank Jones and Frank Fabozzi. How do you measure the risk of a stock portfolio? Absolute risk: Volatility of returns Relative risk: Volatility relative to a benchmark Example: Tracking error or Active risk Definition of Tracking Error Active return = Portfolio return - Benchmark return Tracking error = standard deviation of active returns Application: Information ratio = alpha / tracking error (Alpha = average active return) Estimation of tracking error: - Trailing active returns (backward looking estimate) - Risk model e.g., Barra (forward looking estimate) A Measure of Risk An important risk metric for portfolios that are managed versus a benchmark Typical values: - 0% for index funds - less than 2% for enhanced index funds - 5% for active large cap stock funds Today One year from now Time Cumulative Return Tracking Error = 4% Benchmark Cumulative Return Rtn(Benchmark) Rtn(BM) +4% Rtn(BM) -4% 1 Std Dev or 66% confident Tracking Error: An Example Tracking Error = 1% Today Time Cumulative Return Benchmark Cumulative Return Rtn(Benchmark) Rtn(BM) +1% Rtn(BM) -1% 1 Std Dev or 66% confident One year from now Tracking Error: An Example Determinants of tracking error Number of stocks held - those in the benchmark and those not in the benchmark Size or Style or Sector bets Beta Benchmark volatility Effect of number of stocks Tracking error falls as the portfolio includes more and more of the stocks in the benchmark An optimally constructed portfolio of just 50 stocks can track the SP 500 within 2% Tracking error rises as the portfolio starts to include stocks that are not in the benchmark Tracking Error is Reduced as More Benchmark Stocks are Included Tracking Error Reduction