U.S. stocks fell Thursday ahead of the final trading day of 2021.
The Dow Jones Industrial Average shed 90.55 points, or 0.3%, at 36,398.08. The S&P 500 dipped 0.3% to 4,778.73. The Nasdaq Composite lost 0.2% at 15,741.56.
The end of the year is a historically strong time for stocks, which has been dubbed the "Santa Claus rally." However, the period can bring volatility due to thin trading volume.
"The volumes have been low. I'm attributing a lot of this run ... in the last week to seasonality — the proverbial Santa Claus rally," Jason Snipe, Odyssey Capital Advisors founder and chief investment officer, told CNBC's "Halftime Report."
Biogen slid roughly 8% on Thursday after Samsung denied a report in The Korea Economic Daily that it was in talks to buy Biogen. The stock led decliners on the S&P 500 and Nasdaq Composite. Biogen shares had surged 9.5% on Wednesday on the report.
Weak performance from semiconductor stocks weighed on the S&P 500 and Nasdaq Composite. Micron Technology fell 2.4% and AMD dipped 2.1%. On Wednesday, Micron warned Covid closures in China are impacting the company's production output.
Cruise line stocks took a hit after the Centers for Disease Control and Prevention recommended Americans avoid cruise travel regardless of vaccination status. Norwegian Cruise Line retreated 2.6% and Carnival lost 1.3%.
Some travel-related stocks rebounded Thursday after seesawing in trading this week as investors monitor developments with the omicron Covid variant. Penn National Gaming gained 4.5% and led the S&P 500.
On the data front, jobless claims last week came in lower than expected, the Labor Department reported Thursday. Initial claims totaled 198,000 for the week ended Dec. 25, while economists surveyed by Dow Jones projected 205,000.
This year has seen the second-highest number of record closes for the S&P 500 during a calendar year at 70 closing highs, trailing just 1995's 77.
All three major averages are up for the month of December. The S&P and Dow are on pace for a second positive month in the last three, while the Nasdaq Composite is on track for a third straight month of gains.
For the year, the S&P is up more than 27% and the Dow is up nearly 10%. The Nasdaq has gained roughly 22%, while the Russell 2000 is up about 14%.