Shares of Nio Inc. /zigman2/quotes/204905836/composite NIO -7.30% were vaulted 21% higher in premarket trading Monday, after DigiTimes reported that the China-based electric vehicle (EV) maker recorded a big jump in sales in June. The rally puts the stock on track for a fifth-straight gain, to the highest price seen during regular session hours since Sept. 14, 2018, which was Nio's third day as a public company; the stock's record close was $11.60 on Sept. 13, 2018. The stock rocketed 35.9% over the past four sessions through Thursday. DigiTimes reported Monday, citing industry sources, that Nio sold 3,740 EVs in June, up 179% from a year ago. The report follows rival Tesla Inc. /zigman2/quotes/203558040/composite TSLA -3.09% reporting on Thursday second-quarter deliveries that were well above expectations. Nio's stock has more than doubled year to date through Thursday (up 133%), while Tesla shares have nearly tripled (up 189%) and the S&P 500 /zigman2/quotes/210599714/realtime SPX +1.22% has slipped 3.1%.