24-Month SMA Effectiveness Verification Tests
March 10, 2016 - Technical Trading
“Pervasiveness and Robustness of SMA Effectiveness for Stocks” summarizes research finding that long-term simple moving averages (SMA) pervasively outperform a buy-and-hold approach for U.S. stocks and stock portfolios during 1960-2011 and for seven developed stock markets during 1975-2010. Does this research, which focuses on a 24-month SMA, discover some essential cyclical nature of equity markets? To verify, we test the effectiveness of a 24-month SMA timing strategy versus a buy-and-hold approach for three U.S. stock market series: (1) SPDR S&P 500 (SPY); (2) the underlying S&P 500 Index (augmented with dividend yields estimated from Robert Shiller’s data); and, (3) the Dow Jones Industrial Average (DJIA). The limiting input for the third test is availability of a U.S. Treasury bills (T-bill) yield. The 24-month SMA strategy shifts to stocks (T-bills) when the monthly close crosses above (below) the 24-month SMA. We also test both a 23-month intrinsic momentum strategy, which is in stocks (T-bills) when the lagged 23-month return is positive (negative), and a comparable 10-month SMA strategy. For all timing strategies, we assume an investor can slightly anticipate signals and execute trades at the same close. Using monthly returns for SPY since January 1993 (dividend-adjusted), the S&P 500 Index with dividend yields from Shiller since January 1950 and DJIA since January 1932, along with contemporaneous monthly 3-month T-bill yields, all through January 2016, we find that: Keep Reading