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.
January 4, 2021 - Calendar Effects, Political Indicators
Do investors swing toward optimism around U.S. presidential inauguration days, focusing on future opportunities? Or, does the day remind investors of political uncertainty and conflict? To investigate, we analyze daily returns of the S&P 500 Index around inauguration day. We consider subsamples of no party change and party change. Using inauguration dates since 1928 and daily S&P 500 Index levels during 1928 through 2020, we find that: Keep Reading
December 9, 2020 - Calendar Effects, Equity Options, Momentum Investing
Do options of individual stocks exhibit momentum and seasonality patterns? In their November 2020 paper entitled “Momentum, Reversal, and Seasonality in Option Returns”, Christopher Jones, Mehdi Khorram and Haitao Mo investigate momentum and seasonality effects for options on U.S. common stocks. They focus on performance of straddles, combining a put and a call with the same strike price and expiration date. They balance needs for liquidity and sample size by requiring positive open interest during the holding period but not the momentum calculation interval. Specifically, on each monthly option expiration date, they:
- Form two straddles from near-the-money options expiring next month for each for each stock: (1) the pair with call delta closest to 0.5 for calculating momentum; and, (2) the pair with call delta closest to 0.5 and with positive open interest for both the put and the call when selected for calculating momentum portfolio return.
- Construct from these pairs zero-delta straddles using bid-ask midpoints as prices and calculate monthly straddle excess returns relative to the 1-month Treasury bill yield. This process generates about 1,600 straddles per month with average monthly excess return -5.6% and very large standard deviations.
- Calculate momentum as average monthly excess return over a specified lookback interval (rather than cumulative return, to suppress effects of return outliers).
- Rank straddle returns into equal-weighted fifths (quintiles) based on momentum and calculate average return for each quintile and for a portfolio that is long the top quintile and short the bottom quintile.
Using end-of-day open interest and bid-ask quotes for call and put options on U.S. common stocks from OptionMetric and trading data for underlying stocks during January 1996 through June 2019, they find that: Keep Reading
December 2, 2020 - Calendar Effects, Commodity Futures
Does crude oil (an important part of commodity indexes) exhibit an exploitable price seasonality? To check, we examine three monthly series:
- Spot prices for West Texas Intermediate (WTI) Cushing, Oklahoma crude oil since the beginning of 1986 (34+ years).
- Nearest expiration futures prices for crude oil since April 1983 (37+ years).
- Prices for United States Oil (USO), an exchange-traded implementation of short-term crude oil futures since April 2006 (14+ years).
We focus on average monthly returns by calendar month and variabilities of same. Using monthly prices from respective inceptions of these series through October 2020, we find that: Keep Reading
November 16, 2020 - Calendar Effects, Equity Premium
Does the U.S. stock market respond predictably to simultaneous earnings announcements of attention-grabbing companies? In their September 2020 paper entitled “Famous Firms, Earnings Clusters, and the Stock Market”, Yixin Chen, Randolph Cohen and Zixuan Wang examine U.S. stock market (E-mini S&P 500 futures) responses to earnings announcement clusters (EAC) comprised of high-attention firms. They focus on the three most prominent pre-open (AM) and three most prominent post-close (PM) EACs in each of January, April, July and October, with each announcement weighted for prominence by associated total number of Dow Jones earnings news articles during the prior calendar year. Using earnings announcements and daily prices for S&P 500 components and minute-by-minute E-mini S&P 500 futures returns during 1999-2018, and associated earnings news articles during 1998-2018, they find that: Keep Reading
July 13, 2020 - Calendar Effects
The Trading Calendar presents cumulative return visualizations for the S&P 500 Index across the calendar year and across each calendar month. Three alternative perspectives on U.S. stock market performance by calendar month are: (1) percentage of positive returns; (2) ratio of average return to standard deviation of returns; and, (3) distribution of returns. Using monthly returns for the S&P 500 Index during January 1928 through December 2019 (92 observations per month), we find that: Keep Reading
March 27, 2020 - Calendar Effects, Momentum Investing
Are some calendar months more likely to exhibit stock market continuation or reversal than others, perhaps due to seasonal or fund reporting effects? In other words, is intrinsic (times series or absolute) momentum an artifact of some months or all months? To investigate, we relate U.S. stock index returns for each calendar month to those for the preceding 3, 6 and 12 months. Using monthly closes of the S&P 500 Index since December 1927 and the Russell 2000 Index since September 1987, both through January 2020, we find that: Keep Reading
March 24, 2020 - Calendar Effects, Equity Premium
Has 24-hour trading of equity index futures created a reliable pattern in hour-by-hour returns? In their February 2020 preliminary paper entitled “The Overnight Drift”, Nina Boyarchenko, Lars Larsen and Paul Whelan study round-the-clock U.S. stock market performance decomposing S&P 500 Index futures returns by hour, with focus on dealer inventory management. Using 24-hour high-frequency trades and quotes for S&P 500 futures contracts during January 1998 through December 2018, they find that: Keep Reading
March 4, 2020 - Bonds, Calendar Effects
As implied in “Mirror Image Seasonality for Stocks and Treasuries?”, are bonds better than stocks during the “Sell-in-May” months of May through October? Are behaviors of government, corporate investment grade and corporate high-yield bonds over this interval similar? To investigate, we test seasonal behaviors of:
SPDR S&P 500 (SPY)
Vanguard Intermediate-Term Treasury (VFITX)
Fidelity Investment Grade Bond (FBNDX)
Vanguard High-Yield Corporate Bond (VWEHX)
Using dividend-adjusted monthly prices for these funds during January 1993 (limited by SPY) through January 2020, we find that: Keep Reading
February 27, 2020 - Bonds, Calendar Effects, Equity Premium, Strategic Allocation
How does execution delay affect the performance of the Best Value and Weighted versions of the “Simple Asset Class ETF Value Strategy” (SACEVS)? These strategies each month allocate funds to the following asset class exchange-traded funds (ETF) according to valuations of term, credit and equity risk premiums, or to cash if no premiums are undervalued:
3-month Treasury bills (Cash)
iShares 20+ Year Treasury Bond (TLT)
iShares iBoxx $ Investment Grade Corporate Bond (LQD)
SPDR S&P 500 (SPY)
To investigate, we compare 22 variations of each strategy with execution days ranging from end-of-month (EOM) per the baseline strategy to 21 trading days after EOM (EOM+21). For example, an EOM+5 variation computes allocations based on EOM but delays execution until the close five trading days after EOM. We include a benchmark that each month allocates 60% to SPY and 40% to TLT (60-40) to see whether variations are unique to SACEVS. We focus on gross compound annual growth rate (CAGR), maximum drawdown (MaxDD) and annual Sharpe ratio as key performance statistics. Using daily dividend-adjusted closes for the above ETFs from the end of July 2002 through January 2020, we find that:
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January 15, 2020 - Calendar Effects, Equity Premium, Fundamental Valuation, Technical Trading
Are there any seasonal, technical or fundamental strategies that reliably time the U.S. stock market as proxied by the S&P 500 Total Return Index? In the February 2018 version of his paper entitled “Investing In The S&P 500 Index: Can Anything Beat the Buy-And-Hold Strategy?”, Hubert Dichtl compares excess returns (relative to the U.S. Treasury bill [T-bill] yield) and Sharpe ratios for investment strategies that time the S&P 500 Index monthly based on each of:
- 4,096 seasonality strategies.
- 24 technical strategies (10 slow-fast moving average crossover rules; 8 intrinsic [time series or absolute] momentum rules; and, 6 on-balance volume rules).
- 18 fundamental variable strategies based on a rolling 180-month regression, with 1950-1965 used to generate initial predictions.
In all cases, when not in stocks, the strategies hold T-bills as a proxy for cash. His main out-of-sample test period is 1966-2014, with emphasis on a “crisis” subsample of 2000-2014. He includes extended tests on seasonality and some technical strategies using 1931-2014. He assumes constant stock index-cash switching frictions of 0.25%. He addresses data snooping bias from testing multiple strategies on the same sample by applying Hansen’s test for superior predictive ability. Using monthly S&P 500 Index levels/total returns and U.S. Treasury bill yields since 1931 and values of fundamental variables since January 1950, all through December 2014, he finds that:
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