Tesla’s disappointing delivery results show how hard it is getting to sell electric vehicles—and explain why the stock has sunk more than 20% since peaking in December.The stock, however, was rebounding early Friday,

After a monstrous stock rally following November’s presidential election, Tesla (TSLA) reported its first annual decline in electric vehicle delivery, highlighting the growing disconnect between its high-flying stock price and its core automobile business.

Shares of Tesla Inc. slid 6.08% to $379.28 Thursday, on what proved to be an all-around grim trading session for the stock market, with the NASDAQ Composite Index falling 0.16% to 19,280.79 and Dow Jones Industrial Average falling 0.