Wall Street stock indexes opened higher in the first trading session of the new year. Here’s what we’re watching in Monday’s action:

• Tesla shares jumped 8.4% in early trading. The electric-vehicle maker said Sunday that it delivered more than 936,000 vehicles globally in 2021, up from nearly half a million the previous year. Shares of fellow EV maker Lucid Group also got a jolt, adding 2.4%. U.S.-traded shares of Chinese EV maker Nio were also up, by 3.7%.

• Novavax slipped 2% in opening trading. The vaccine maker on Friday said it had provided the final required data to the Food and Drug Administration so that it could apply for emergency use authorization for its Covid-19 vaccine.
• Exxon Mobil gained 0.9%. The oil-and-gas producer released an update of factors impacting its fourth-quarter profits that suggests a likely earnings beat when it reports on Feb. 1.
• Naked Brand Group added 2.2%. The intimate apparel company said Friday it had completed its previously announced acquisition of closely held electric-vehicle company Cenntro. Once the acquisition was completed, the company changed its name to Cenntro Electric Group.

Chart of the Day

• Stock markets in China have swelled in valuation, showing how domestic shares have largely been immune from the regulatory assault that has rocked many companies listed abroad.

Write to James Willhite at james.willhite@wsj.com