Both the Dow Jones Industrial Average and the are on pace for their worst December performance since 1931, when stocks were battered during the Great Depression. The Dow and S&P 500 closed Monday down 7.6 percent and 7.8 percent this month , respectively.

Two benchmark U.S. stock indexes are careening toward a historically bad December.

December is typically a very positive month for markets. The Dow has only fallen during 25 Decembers going back to 1931.

The S&P 500 averages a 1.6 percent gain for December, making it typically the best month for the market, according to the Stock Trader's Almanac.

While the S&P 500 began dissemination in 1950, the performance data was backtested through 1928. It's worth noting that historically, the second half of December tends to see gains.

– CNBC's Gina Francolla contributed to this report.

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