Wall Street closed in negative territory Monday in light volume at the top of a holiday-shortened week in the second-to-last trading session of an eventful year in which all three indexes posted strong double-digit gains.

End-of-year tax positioning, valuations, climbing Treasury yields and uncertainties about 2025 all contributed to the risk-off sentiment. The three major U.S. stock indexes bounced off early lows but still were down more than 0.5%.

"Investors are saying the S&P, even after this recent sell off, is up over 50% in the last two years," said Oliver Pursche, senior vice president at Wealthspire Advisors, in New York. "Maybe we should take some chips off the table and protect those gains. And when you have thin volume, it doesn’t take a lot (to move markets)."

Despite recent weakness, 2024 has been a banner year for U.S. equities. The Nasdaq is on track for about a 30% annual gain and the S&P 500 is headed for just over a 24% rise for 2024. The Dow remains up just over 13% from the last closing levels of 2023.

On the sector level, technology, communication services and consumer discretionary were on course to notch gains of nearly 30% or more, while materials appear poised to nab the dubious distinction of the only sector to have lost ground on the year.

It was a year during which geopolitical tensions came to a boil in the Middle East and elsewhere, while the Federal Reserve cut U.S. interest rates for the first time in over four years.

In U.S. politics, former President Donald Trump was convicted of 32 felonies early in the year, then won re-election to a second term after President Joe Biden dropped out of the race to be replaced as Democratic candidate by Vice President Kamala Harris.

Chip maker Nvidia's stock shot up nearly 180% this year as investors placed heavy bets on the promise of emergent artificial intelligence (AI) technology. In November, Nvidia replaced rival chip maker Intel in the Dow Jones Industrial Average.

"Next year is going to be much more volatile for investors, in particular in the first quarter," Pursche added. "However, I do think there’s a good chance of stocks doing reasonably well and having mid-single-digit returns next year."

"The combination of likely lower taxes and a friendlier regulatory environment is likely to result in stocks rising well beyond fair valuations," Pursche said, citing investor expectations that Trump will deliver on his campaign promises.

According to preliminary data, the S&P 500 lost 63.95 points, or 1.06%, to end at 5,907.43 points, while the Nasdaq Composite lost 235.25 points, or 1.19%, to 19,486.79. The Dow Jones Industrial Average fell 410.18 points, or 0.95%, to 42,582.03.

Boeing shares fell after South Korea's acting president Choi Sang-mok ordered an emergency safety inspection of its entire airline operation following the deadliest air accident in that country's history, involving a Boeing 737-800.

Crypto stocks including MicroStrategy Coinbase and MARA Holdings tumbled.

Biden declared a national day of mourning on Thursday Jan. 9 to mark the death on Sunday of former President Jimmy Carter.

The U.S. stock market will be closed that day.