Irish folk legends say that leprechauns guard pots of gold. But real-life wealth-seekers are better off throwing themselves into the stock market on St. Patrick’s Day.
That’s because on a historical basis, the S&P 500 stock market index has been more likely to rise on St. Patrick’s than on the vast majority of other days in the year, according to an analysis published this week by advisory firm LPL Financial.
Over the past 20 years, the S&P 500 has risen 80% of the time on St. Patrick’s Day. That also makes March 17 one of the 10 most consistently positive calendar days for the S&P 500 over the past two decades, beaten only by July 3 (positive 81.8% of the time), July 13 (85.7%), Aug. 17 (85.7%), Sept. 16 (86.7%), and Dec. 26 (81.8%).
Moreover, average returns from the S&P 500 on St. Patrick’s are quite high compared to the other trading days of the year. On the day celebrating all things Irish, the S&P 500 has returned an average 0.72% over the past 20 years. Those returns may not sound that impressive, but it is the eighth highest average S&P 500 daily return since 1997.
In fact, the entire month of March has historically been the best month for stocks over the past decade, according to LPL. On average, the S&P 500 has returned 2.7% in the month of March.
Why the outperformance in March? According to LPL Senior Market Strategist Ryan Detrick, it may have something to do with the Internal Revenue Service’s tax refund schedule. The tax authority generally begins distributing refunds from the previous years tax returns in February, freeing up dollars that could be placed in the stock market starting around March.
Markets on Thursday didn’t seem to be building momentum for a green St. Patrick’s Day, with the S&P 500 down slightly at 0.16% and the down also down 0.07%.
Friday will mark the start of the two-day meeting of G20 finance ministers, where all eyes will be on U.S. Treasury Secretary Steven Mnuchin and his trade rhetoric. Most are expecting Mnuchin to set a slightly less protectionist tone than President Donald Trump. The University of Michigan is also expected to publish its monthly Consumer Sentiment Index on Friday.
There’s one more reason to choose equities over the leprechaun’s riches come St. Patrick’s Day. Over a 20-year span, the price of gold has generally dipped on the holiday, according to data from FactSet. Gold has fallen an average of 0.02% on March 17 over the past two decades, and has risen just 44% of the time.
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