Turn-of-the-Month Effect Persistence and Robustness

Is the Turn-of-the-Month (TOTM) effect, a concentration of relatively strong stock market returns around the turns of calendar months, persistent over time and robust to different market conditions. Does it exist for all calendar months? Does it persist throughout the U.S. political cycle? Does it work for different equity indexes? To investigate, we define TOTM as the interval from the close five trading days before to the close four trading days after the last trading day of the month (a total of eight trading days, centered on the monthly close). Using daily closes for the S&P 500 Index since January 1928 and for the Russell 2000 Index since mid-September 1987, both through early January 2024, we find that: (more…)