(Reuters) - Tesla Inc TSLA.O said on Thursday production and deliveries of its Model Y sport utility vehicle was significantly ahead of schedule, as the company delivered the highest number of vehicles in any first quarter to date.

FILE PHOTO: Tesla Inc CEO Elon Musk attends an opening ceremony for Tesla China-made Model Y program in Shanghai, China January 7, 2020. REUTERS/Aly Song

The company’s solid deliveries despite the coronavirus outbreak in the United States sent its shares up about 15% in extended trading.

The company’s production and delivery was largely unaffected by the coronavirus outbreak in the first three months of the year, as Tesla only began to temporarily suspend production at its San Francisco Bay Area vehicle factory on March 24.

Tesla on Thursday did not address the impact of the coronavirus pandemic.

The electric carmaker said Model Y production started in January and deliveries began in March, significantly ahead of schedule.

Webush analyst Daniel Ives described the deliveries as “better than feared in a COVID-19 environment,” referring to the potentially lethal respiratory illness caused by the coronavirus.

“It appears China production and demand are starting to rebound and should be a key growth driver over the coming quarters, although clear challenges remain in the months ahead,” he added.

Demand for the Model Y is expected to be higher than for all of Tesla’s other models combined, Chief Executive Elon Musk has said in the past. The Model Y taps into strong demand for SUVs and is much less expensive than the high-end Model X.

But the coronavirus-related shutdown at its California factory is likely to affect production of the Model Y going forward.

It also said that its Shanghai factory in China continued to achieve record levels of production, despite significant setbacks.

The company delivered 88,400 vehicles in the first quarter, including 76,200 Model 3’s and Y’s and 12,200 Model S’s and X’s.