In part, the company says, the shortfall came because so many vehicles—5,150—were still in delivery at the end of the quarter, and will be delivered early in the third quarter. In total, 18,345 vehicles were produced for the quarter, an increase of 20% from Q1. Tesla is now producing just under 2,000 vehicles a week.

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The Model X ramp-up was a bright spot, with the company meeting its previous goal of producing roughly 1,000 Model Xs per week by the end of the second quarter, after experiencing early production problems on the new model.

Tesla now says it expects to produce and deliver about 50,000 vehicles during the second half of 2016. That would still put it just shy of its goal, laid out in February, of delivering between 80,000 and 90,000 vehicles for the year. A little over 50,000 cars were delivered for all of 2015.

The company has said it aims to continue ramping up, with a goal of delivering 500,000 cars a year by 2018. Tesla has told suppliers that as many as 400,000 of cars produced that year will be Model 3s, the new mid-market vehicle introduced to ravenous demand earlier this year. It is projected to begin delivery in 2017.

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CEO Elon Musk has said Tesla learned an important lesson from the “excruciating” challenges of producing the overcomplicated Model X, and that the Model 3 will begin life as a more streamlined, easier-to-build product. But suppliers have already signaled that the 2018 production goals will be a challenge, and Musk has explained that the company knowingly sets production targets that are nearly impossible to meet.