How Many Tesla Model S Electric Cars Have Been Built So Far?

Car production data may cause some eyes to glaze over, but the numbers are closely followed in the auto industry.

Electric-car maker Tesla Motors doesn't report its exact sales, nor its precise production, so a cottage industry has sprung up to track its alleged production.

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Among other things, at its Detroit Auto Show press conference yesterday, Tesla executives said the company had delivered "almost 6,900 cars" during the fourth quarter of 2013.

That was roughly 20 percent higher than the guidance Tesla had provided on an October conference call to discuss its third-quarter financial results.

And it's a sign that the company is continuing to streamline its production process, removing bottlenecks and smoothing the steady flow of components into its plant in Fremont, California.

While Tesla has not said how many of those 6,900 cars were sold in the United States--we would expect to learn that next month on its next conference call--the company likely sold between 18,000 and 20,000 Model S cars in the U.S. during 2013.

Added to that are about 2,600 sold in 2012, plus several thousand more delivered to European buyers starting last August.

A long thread recording Tesla Model S serial numbers was recently removed by its creator from the Tesla Motors Club forum because, he said, financial analysts were using it for purposes he wasn't comfortable with, as well as calling to interrogate him about the meaning of the data.

Still, Tesla itself tends to tease its numbers. On a slide shown during the company's press conference yesterday, the following bullet point appeared: "More than 25,000 Model S on the road today."