Calendar Effects
The time of year affects human activities and moods, both through natural variations in the environment and through artificial customs and laws. Do such calendar effects systematically and significantly influence investor/trader attention and mood, and thereby equity prices? These blog entries relate to calendar effects in the stock market.
April 23, 2024 - Calendar Effects
Is the stock market overnight move effect exploitable? To investigate, we look at performances of two exchange-traded funds (ETF) designed to exploit the effect:
- NightShares 500 ETF (NSPY), which “seeks to return the night performance of a portfolio of 500 large cap U.S. companies.” The benchmark is SPDR S&P 500 ETF Trust (SPY).
- NightShares 2000 ETF (NIWM), which “seeks to return the night performance of a portfolio of 2000 small cap U.S. companies.” The benchmark is iShares Russell 2000 ETF (IWM).
Because available samples are short, we focus on daily return correlation with the benchmark, average daily return, standard deviation of daily returns and daily reward/risk (average daily return divided by standard deviation of daily returns). We also look at compound annual growth rates (CAGR) and maximum drawdowns (MaxDD) based on daily data. Using daily total returns for NSPY, NIWM and benchmarks during June 28, 2022 through July 31, 2023, we find that: Keep Reading
April 17, 2024 - Calendar Effects
How has the simple Sell in May strategy worked in the modern U.S. equity market, defined as the time since introduction of SPDR S&P 500 ETF Trust (SPY)? To investigate, we:
- Calculate 6-month SPY returns from the ends of April and October.
- Find yields for 6-month U.S. Treasury bills (T-bills) at the end of each April, and the yield for 3-month T-bills at the end of January 1993 for the initial interval.
- Generate returns for a strategy that holds SPY during November through April and T-bills during May through October, with switches at the ends of April and October.
We assume 0.1% frictions when switching between SPY and T-bills. We ignore tax implications of trading. The benchmark is buy-and-hold SPY. Using the specified data from the end of January 1993 through March 2024, we find that: Keep Reading
March 26, 2024 - Calendar Effects
Is the behavior of the U.S. stock market around exchange holidays consistent enough to generate an aggregate pattern? To investigate, we look at daily S&P 500 Index returns from three trading days before a holiday through three trading days after for the following holidays (adding the Super Bowl) as available since 1950:
New Year’s Day (74 observations, including 2024)
Super Bowl (58 observations, including 2024)
Good Friday (74 observations)
Memorial Day (53 observations)
4th of July (74 observations)
Labor Day (74 observations)
Thanksgiving (74 observations)
Christmas (74 observations)
The total number of observations is 555. Using daily closes of the S&P 500 Index during the specified intervals around holidays, we find that: Keep Reading
March 4, 2024 - Bonds, Calendar Effects
Does iShares 20+ Year Treasury Bond ETF (TLT) exhibit a predictable monthly pattern due to beginning-of-month dividends and mid-month U.S. government consumer and producer inflation releases? To investigate, we calculate average cumulative return for TLT across the month (from trading day 1 through trading day 23). We also investigate exploitability of findings. Using daily raw and dividend-adjusted levels of TLT from the end of July 2002 (inception) through January 2024 (21.5 years), we find that: Keep Reading
January 23, 2024 - Calendar Effects, Technical Trading
“Turn-of-the-Month Effect Persistence and Robustness” indicates that average absolute returns during the turn-of-the-month (TOTM) are strong for both bull and bear markets. Does a strategy of capturing all bull market returns and TOTM returns only during bear markets perform well? To investigate, we apply four strategies to SPDR S&P 500 ETF Trust (SPY) as a tradable proxy for the stock market:
- SPY – buy and hold SPY.
- SMA200 – hold SPY (cash) when SPY closes above (below) its 200-day simple moving average (SMA200) the prior day.
- TOTM – hold SPY from the close five trading days before through the close four trading days after the last trading day of each month and cash at all other times (TOTM).
- SMA200 or TOTM – hold SPY when SPY closes above its 200-day SMA the prior day and otherwise use the TOTM strategy.
We explore sensitivities of these strategies to a range of one-way SPY-cash switching frictions, with baseline 0.1%. Using daily dividend-adjusted SPY from the end of January 1993 through early January 2024 and contemporaneous 3-month Treasury bill (T-bill) yields as the return on cash, we find that: Keep Reading
January 22, 2024 - Calendar Effects
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: Keep Reading
January 18, 2024 - Calendar Effects
Does long term data support the belief that “as goes January, so goes the rest of the year” (January is the barometer) for the the U.S. stock market? To investigate, we consider two views of the S&P 500 Index over its full history:
- Correlations between index returns during each calendar month and returns over the next 11 months.
- Index performance during the next 11 months across ranked thirds (terciles) of January returns.
Using monthly closes of the S&P 500 Index from the end of 1927 through 2023 (96 years), we find that: Keep Reading
January 12, 2024 - Calendar Effects
Are some years of the decade better than others for equity markets? To investigate, we look at average annual returns by year of the decade (xxx0 through xxx9) for the U.S. stock market. Using annual levels of Shiller’s S&P Composite Index for 1871-2023 and the S&P 500 Index for 1928-2023, we find that: Keep Reading
November 13, 2023 - Calendar Effects, Strategic Allocation
A subscriber requested testing of a strategy that holds a combination of 50% Simple Asset Class ETF Value Strategy (SACEVS) Best Value and 50% Simple Asset Class ETF Momentum Strategy (SACEMS) equal-weighted (EW) Top 2 strategies during November through April and idle cash during May through October. We consider three strategies:
- Best Value – EW Top 2 – hold Best Value-EW Top 2 during all months.
- Best Value – EW Top 2 Seasonal (Idle Cash) – hold Best Value-EW Top 2 during November through April and idle cash during May through October, as requested.
- Best Value – EW Top 2 Seasonal (6-month T-bill) – hold Best Value-EW Top 2 during November through April and 6-month U.S. Treasury bills (T-bill) bought at the beginning May each year during May through October.
We run annual statistics for each variation as in “Combined Value-Momentum Strategy (SACEVS-SACEMS)”. Annualized returns are compound annual growth rates. Maximum drawdown is the deepest peak-to-trough drawdown for these strategies based on monthly measurements over the sample period. For Sharpe ratio, to calculate excess annual return, we use average monthly yield on 3-month Treasury bills during a year as the risk-free rate for that year. Using monthly returns for SACEVS Best Value and SACEMS EW Top 2 and the specified T-bill yield during July 2006 through October 2023, we find that: Keep Reading
November 6, 2023 - Calendar Effects
A subscriber requested a test of holding Invesco QQQ Trust (QQQ) during November through April and idle cash during May through October. Informed by the Trading Calendar, we consider four strategies:
- QQQ – buy and hold QQQ.
- QQQ Seasonal (Idle Cash) – hold QQQ during November through April and idle cash during May through October, as requested.
- QQQ No-even (Idle Cash) – hold QQQ during odd years and idle cash during even years (avoiding stocks during years with U.S. federal elections).
- QQQ No-even (1-year T-note) – hold QQQ during odd years and 1-year U.S. Treasury notes (T-note) bought at the beginning of the year during even years.
We consider average monthly return, standard deviation of monthly returns, monthly reward/risk (average return divided by standard deviation), compound annual growth rate (CAGR) and maximum drawdown (MaxDD). We ignore frictions and tax implications of trading once or twice a year. Using monthly dividend-adjusted returns for QQQ during March 1999 (inception) through October 2023, we find that: Keep Reading