The S&P 500 reached a new pandemic recovery milestone on Monday: the benchmark has rallied 100% from its COVID low of 2,237.40 on March 23, 2020 on a closing basis. With a new record close on Monday, the benchmark rose from its bottom in just 354 trading days.

By the sector, nearly two-thirds of S&P 500 sectors have doubled throughout the bull market, with Materials (XLB  ), Information Technology (XLK  ), Financials (XLF  ) and Industrials (XLI  ) all rising over 115%.

Here's how the market settled on Monday:

S&P 500 Index (SPY  ): +0.26% or +11.71 points to 4,479.71

Dow Jones Industrial Average (DIA  ): +0.31% or +110.02 points to 35,625.40

Nasdaq Composite Index (QQQ  ): -0.20% or -29.13 points to 14,793.76

Pfizer, BioNTech submit early-stage booster vaccine data to FDA:

Pfizer (PFE  ) and BioNTech (BNTX  ) announced Monday the pair have submitted early-stage clinical trial date to the Food and Drug Administration to support their U.S. application seeking emergency authorization of a third booster shot of its COVID vaccine for Americans 16 and older.

"The data we've seen to date suggest a third dose of our vaccine elicit antibody levels that significantly exceed those seen after the two-dose primary schedule," Pfizer CEO Albert Bourla said in a press statement. "We are pleased to submit these data to the FDA as we continue working together to address the evolving challenges of this pandemic."

The companies said late-stage clinical trial results evaluating the third dose are expected in the near-term and will also be submitted to the FDA and other global regulatory authorities.

Walmart looking for cryptocurrency and digital currency product lead:

According to a new listing on the company's website, Walmart (WMT  ) is looking to hire a new senior director to develop new digital currency products, Bloomberg reports.

The new Walmart senior director position is titled "Cryptocurrency and Digital Currency Product Lead," in charge of developing the big box retailers "digital currency strategy and product roadmap." Among other responsibilities, the role will also be focused on identifying crypto "related investment and partnerships," meaning that Walmart may be interested in acquiring or investing in other existing cryptocurrency businesses in the future.

Federal vehicle safety regulator opens probe into Tesla Autopilot:

The National Highway Traffic Safety Administration (NHTSA) announced Monday they have opened a formal safety investigation into Tesla's (TSLA  ) Autopilot system following a series of crashes that resulted in at least 17 injured people and one death.

Since January 2018, the federal vehicle safety regulator has identities 11 crashes which involved Tesla models striking vehicles in first responder scenes. "Most incidents took place after dark and the crash scenes encountered included scene control measures such as first responder vehicle lights, flares, an illuminated arrow board, and road cones," the NHTSA document reads. "The involved subject vehicles were all confirmed to have been engaged in either Autopilot or Traffic Aware Cruise Control during the approach to the crashes."

The probe will evaluate the Autopilot in Tesla vehicles made between 2014 and 2021.

Here's how markets started trading soon after market open:

S&P 500 Index: -0.30% or -13.48 points to 4,454.52

Dow Jones Industrial Average: -0.33% or -117.44 points to 35,397.94

Nasdaq Composite Index: -0.33% or -48.87 points to 14,774.03