Stocks on track for worst December since the Great Depression

The Dow and S&P 500 were each down about 7.8% through Monday. That's the largest drop for each key market barometer since 1931, according to data from LPL Research. But those Depression-era losses were much bigger: the S&P 500 plunged 14.5% while the Dow plunged 17%.

Still, the December 2018 swoon is making investors nervous that earnings growth may have peaked this year. They're worried that the economy could slow in 2019 because of continued trade tensions with China and rate hikes by the Federal Reserve.

The Dow and S&P 500 are both in the red for the year, putting stocks on track to have their worst annual loss since the 2008 Great Recession — and first annual loss since 2015.

But investors can still hope that the markets will turn around in the month's (and year's) final days.

December is usually a very solid month for the market. Professional money managers tend to buy top-performing stocks to make their portfolios look good — a phenomenon known as window dressing.

There's also the somewhat mysterious Santa Claus rally effect. The market tends to do well in the final week of the year, which some chalk up to light trading volume with so many people off for the Christmas holiday.

To that end, stocks did rise a little more than 1% Tuesday morning.

So as of right now, the market's current monthly losses are more on par with the poor market performance of December 2002, when the Dow and S&P 500 each fell more than 6%.