Tesla shares slump as it joins the S&P500 index

Company makes up 1.69 per cent of the benchmark but dropped 5 per cent on first day of inclusion

Customers and staff at a Tesla showroom in Shanghai, China. The California-based electric vehicle maker's recent stock surge has put its market value at about $630 billion. Bloomberg

Shares of electric carmaker Tesla slumped in their debut on the S&P 500 on Monday, pulling back from record-high levels, as worries over a fast-spreading new coronavirus strain in Britain weighed on markets.

Tesla’s shares sank 5 per cent to $659.99 half an hour into the session. In its first day in the S&P 500, the stock was one of the biggest drags on the benchmark index, which was down 1.2 per cent.

The company, headed by billionaire Elon Musk, becomes the most valuable ever admitted to Wall Street's main benchmark and accounted for a 1.69 per cent weight in the index ahead of Monday's trading. The shares had surged some 70 per cent in value since mid-November, when Tesla's debut in the S&P 500 was announced.

The shares jumped 6 per cent on Friday in a day of frantic trading ahead of their S&P 500 entry.

Tesla's addition to the S&P 500 led index-tracking funds to buy $90.3 billion of shares by the end of Friday's session so that their portfolios reflected the index, according to S&P Dow Jones Indices' analyst Howard Silverblatt. The change is effective prior to the open of trading on Monday, S&P said earlier in December, and Tesla is replacing Apartment Investment and Management.

"All the buying was done on Friday," said Keith Temperton, a sales trader at Forte Securities. "The news is done now ... the question now is what next."

Mr Silverblatt said for every $11.11 Tesla moves, the S&P 500 changes 1 point, while the S&P's 2021 price/earnings ratio will rise to 22.6 from 22.3.

The dividend yield for the S&P after Tesla's inclusion would fall to 1.53 per cent from 1.56 per cent, he said.

California-based Tesla's stock surge has put its market value at about $630 billion, making it the sixth-most valuable publicly-listed US company, with many investors viewing it as wildly overvalued.

Tesla is by far the most traded stock by value on Wall Street, with $18bn worth of its shares exchanged on average in each session over the past 12 months, easily beating Apple in second place with average daily trades of $14bn, according to Refinitiv.

About a fifth of Tesla's shares are closely held by Musk, the chief executive, and other insiders.