Bitcoin sank to $86,000, pushing down cryptocurrency stocks. MARA Holdings Inc. and Coinbase Global Inc. both down at least 5%.

“The renewed decline in Bitcoin could create some real problems for the stock market,” noted Miller Tabak + Co. chief market strategist Matt Maley, adding that net liquidity drives Bitcoin’s movement.

Traders are expecting manufacturing data after the opening bell, an outdated personal consumption survey, and November’s ADP private payrolls report before the Federal Reserve’s next policy meeting.

Seasonal patterns can boost stocks, according to history. The S&P 500 has had its second-best average return in December, second-lowest volatility, and highest frequency of monthly advances since 1990, according to CFRA chief financial strategist Sam Stovall. Historically, mid- and small-cap indices beat large caps.