https://www.reuters.com/article/us-usa-stocks-tesla/tesla-shares-fall-ahead-of-sp-500-debut-after-hitting-record-on-friday-idUSKBN28V0IL >(Reuters) -Shares of electric carmaker Tesla were down ahead of their debut on the S&P 500 on Monday, as worries over a fast-spreading new coronavirus strain in Britain weighed on markets.