Don't forget to turn your clocks ahead this weekend, for the questionable annual tradition of daylight saving time is upon us.
Every year around this time, we're treated to a regular deluge of warnings about our health and productivity tied to the loss of an hour of sleep. But if there's one thing you should do, it's watch your portfolio for signs of a dropping market.
Since 2007, the S&P 500 dropped an average of 0.24 percent after a weekend of "spring forward." That's far more than the average 0.03 percent drop over non-time change weekends. That's from close of the markets Friday to close Monday, so any effect of the clock shift would be captured.
A study from 2000 showed a similar pattern of stock exchanges with significantly worse returns over the daylight saving weekend than other times during the year. The researchers argued that much of the drop could be attributed to traders' lack of sleep and the general disorder caused by the clocks' change.