By Emily Dattilo

It is barely a month into the new year, but investors are already busy navigating a presidential inauguration, earnings season, and changes within the artificial intelligence landscape.

The Dow Jones Industrial Average has gained 5.8% in January, while the S&P 500 is 3.6% higher, and the Nasdaq 100 is up 3.2%.

Here are the best and worst stocks in the S&P 500 this month:

The top stock in the S&P 500 was Constellation Energy, which gained 35% this month, its best month since February 2024, according to Dow Jones Market Data.

On Jan. 10, Constellation stock soared 25% after the company reached an agreement to buy Calpine, a move that creates the nation's largest clean-energy provider and gives Constellation a broader array of products. The net purchase price of the deal is roughly $26.6 billion, which includes the assumption of debt for Calpine. It gives Calpine, which is privately held, an enterprise value 7.9 times the amount of earnings before interest, taxes, depreciation, and amortization it is expected to generate in 2026.

However, on Jan. 27, shares tumbled 21% amid a broader tech selloff after viral posts indicated Chinese company DeepSeek had recreated OpenAI's technology in the form of its R1 model for only $6 million, compared with the billions of dollars spent by U.S. tech companies.

Other top performers for January include CVS Health, Vistra, GE Aerospace, and KLA Corporation.

The worst stock in the S&P 500 was Edison International, which is down 33% this month, on track for its worst month since March 2000.

Edison is the parent company of Southern California Electric, which has been struggling as wildfires raged across Los Angeles.

In an electric safety incident report filed Jan. 10, SoCal noted a downed power line was discovered at a tower near the Hurst fire, but said it "does not know whether the damage observed occurred before or after the start of the fire." Earlier this month, in an effort to curb the fires, the company began shutting off power to some customers in the state.

Other worst performers for this month include PG&E Corporation, Constellation Brands, Electronic Arts, and ON Semiconductor.

Write to Emily Dattilo at emily.dattilo@dowjones.com

This content was created by Barron's, which is operated by Dow Jones & Co. Barron's is published independently from Dow Jones Newswires and The Wall Street Journal.

(END) Dow Jones Newswires

January 31, 2025 12:52 ET (17:52 GMT)

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