Bill Gates, already the world’s second-richest person, got an added boost Tuesday as his investment in used-car platform Vroom Inc. more than doubled on the company’s first day of trading.

Shares of New York-based Vroom soared 118 per cent to US$47.90 apiece, lifting the value of Gates’s roughly six per cent holding by more than US$175 million. The Microsoft Corp. co-founder, who owns the stake through Cascade Investment, ended the day with a net worth of US$115.1 billion, according to the Bloomberg Billionaires Index, a ranking of the world’s 500 richest people. He trails only Amazon.com Inc. founder Jeff Bezos, whose fortune climbed by US$4.3 billion on the day to US$156.2 billion.

Vroom, which sells used vehicles online, is also backed by L Catterton, General Catalyst Partners and T. Rowe Price Associates.

It was the second straight day of eye-popping returns for investors in the automotive industry. On Monday, shares of Tesla Inc. competitor Nikola Corp. more than doubled, and the maker of hydrogen-powered trucks climbed an additional 8.8 per cent Tuesday, boosting founder Trevor Milton’s net worth to US$9.8 billion.

While demand for used cars has weakened during the pandemic, Vroom sold more units in March and April than in any previous two-month period, according to filings. Last week, Nikola said pre-orders for its vehicles topped US$10 billion and that it expects to start generating revenue in 2021.