Is a 10-month Moving Average The Best Choice For Momentum Investors?
Momentum investors typically use a filtered version of price to help them determine if an asset has positive or negative momentum. A standard filter is the 10-month Simple Moving Average (SMA10).
The asset is held if the price has positive momentum (above the simple moving average) or sold if it has negative price momentum (is below the simple moving average). Is a SMA10 the best choice of filter? How does overall momentum investment performance vary with filter length?
Below is performance data for a momentum investing approach applied to the S&P 500 from 12/31/71 through 12/31/17 using a simple moving average filter to determine positive and negative momentum versus filter length in months.
The data show that the highest return for a given amount of risk, as measured by the Sharpe Ratio occurs around 11 months - although the overall performance does not vary dramatically.
Disclosure:
The information presented here is the opinion of the author and may quickly become outdated and is subject to change without notice. All material presented in this article are compiled from sources believed to be reliable, however accuracy cannot be guaranteed. No person should make an investment decision in reliance on the information presented here.
The ProFolio model portfolio results presented here are based on simulated or hypothetical performance. Unlike an actual performance record, simulated results do not represent actual trading and there is no market risk involved in the results. The simulated trades use historical data and therefore the trading algorithms are designed with the benefit of hindsight. In a simulated performance record it may be difficult, if not impossible, to account for all factors which might affect an actual performance record. Additionally, any account that ProFolio manages will invest during periods with different economic conditions than those under which the trading programs were developed. There is no representation being made that any account will perform as the hypothetical results indicate. In fact, there are often sharp differences between hypothetical results and actual returns subsequently achieved. Due to the benefit of hindsight, hypothetical performance almost invariably will show attractive returns, while actual results going forward may not be as attractive.
The algorithm that created the trading signals for each of the portfolios used Exchange Traded Fund (ETF) historical data where possible. This ETF data had a limited history. To gain additional data history, the actual asset or index data was pre-pended to the ETF data. When this occurred, ETF expenses were subtracted from the asset or index data. Where asset or index data was not available, other correlated data, adjusted for expenses, was used. Model portfolio results include interest and dividends, but subtract ProFolio's management fee (0.5%) and third-party brokerage custody/trading fee (0.25%). Real returns are inflation adjusted. Higher returns generally come with higher risks. Model portfolio risk characteristics include maximum drawdown and volatility. Maximum drawdown is the portfolio's peak to trough prior to hitting a new peak and is a measure of downside risk. Volatility, or standard deviation, is a measure of the portfolio's price fluctuations both positive and negative. Sharpe ratio is a measure of return for a given risk. Sharpe ratio = (portfolio return - risk free return)/SQRT(portfolio return variance - risk free return variance). Where the risk free asset is the 90-day T-bill and the variance is the square of the standard deviation (or volatility). Tactical portfolios utilize cash or cash equivalents for risk management.
The information presented here is distributed for education purposes only and is not an offer to buy or sell or a solicitation of an offer to buy or sell any security or participate in any particular trading strategy.
