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Trading on Friday the 13th can be frightful

Investors who suffer from triskaidekaphobia or paraskevidekatriaphobia might want to tread carefully when trading on Friday the 13th.

Triskaidekaphobia is the fear of the number 13. Paraskevidekatriaphobia is the fear of Friday the 13th.

The Standard & Poor’s 500 stock index performs worse on Fridays that end in 13 than it does on every other Friday. Since 1928, there have been 152 Friday the 13ths. And the S& P 500 has posted average daily gains of 0.02%, lower than the 0.05% gain for the 4,466 Fridays from 1928 to 2016, according to Ryan Detrick, senior market strategist for LPL Financial, who penned a report, Friday the 13th in October? Oh No! If you annualize those gains, Friday the 13th looks even worse, with a 4.2% gain vs. 12.8% for all Fridays.

If that’s not enough to give an investor pause, Detrick’s analysis shows that the two worst “Friday the 13th” daily returns for the S& P 500 took place in October.

“You can’t make this stuff up. Happy Friday the 13th everyone,” Detrick says.