The new coronavirus variant that emerged in the U.K. is not only more transmissible, but appears to affect a higher proportion of people under 20, according to a new scientific report. The mutation has “a substantial transmission advantage” and is linked to “epidemic growth in nearly all areas,” researchers wrote. Some 83 million people were confirmed to have been infected with the coronavirus in 2020, with 1.8 million fatalities, though the actual numbers are thought to be much higher. The leader in both categories for most of the year has been the U.S., with near one-quarter of all infections and close to one-fifth of all deaths. Here is the latest on the pandemic. —David E. Rovella

Bloomberg is tracking the progress of coronavirus vaccines while mapping the pandemic globally and across America.

Here are today’s top stories

Elon Musk held a $38 billion barbecue of Tesla shorts this year. This “is not only the largest mark-to-market loss for any stock this year,” said Ihor Dusaniwsky, a managing director at S3 Partners. “It is the largest yearly mark-to-market loss I have ever seen.”

The Pentagon has put a decision on approving full-rate production of Lockheed Martin’s $398 billion F-35 fighter program, the subject of numerous design defects and even a criminal investigation, on indefinite hold. The plane has yet to demonstrate its effectiveness against the most challenging Russian and Chinese air defense systems and aircraft. Meanwhile, the U.S. Navy’s plan to deliver on time the first of its $128 billion next-generation missile submarine fleet is at risk because of inexperienced contractors with spotty quality control, a government watchdog warned. And the cost overrun could be as much as $384 million—for the one boat.

An artist's rendering of the future Columbia-class ballistic missile submarine.

Gold is set for the biggest annual advance in a decade, with gains this month aided by the dollar’s decline to the lowest since April 2018. Holdings in bullion-backed exchange-traded funds set an all-time high in October.

Microsoft said the suspected Russian hackers behind the stunning breach of numerous U.S. government agencies also accessed the company’s internal source code.

Record-low mortgage rates were supposed to make it easier for homebuyers. Instead, they’ve helped push affordability to a 12-year low. Buyers in the fourth quarter needed to spend almost 30% of the average wage to afford a typical house, the biggest share for any three-month period since 2008.

A U.K. judge will rule Monday on whether WikiLeaks founder Julian Assange should be extradited to the U.S. to face prosecution after weeks of talk about a possible pardon from President Donald Trump. Assange, who is accused of helping leak classified U.S. documents about the wars in Iraq and Afghanistan, drew praise from the Republican when WikiLeaks released emails that undercut former Secretary of State Hillary Clinton’s presidential campaign.

Julian Assange in a prison van outside a London courthouse on May 1, 2019

In the U.S., the rollout of Covid-19 tests was botched, personal protective equipment remains in short supply and precautions such as masks, social distancing and lockdowns have become politicized. Now, America is attempting a massive vaccination campaign, and things aren’t going well.

What you’ll need to know tomorrow

What you’ll want to read in Bloomberg Opinion

How the Best Stock Picker of the Year Won

Everyone should know Cathie Wood by now, Bloomberg News Editor-in-Chief Emeritus Matthew Winkler writes in Bloomberg Opinion. That’s because whatever benefits central bankers bequeathed to shareholders with next-to-zero interest rates and the record $14 trillion global money supply increase in 2020, Wood beat every stock picker by betting on these innovators.

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