If you’ve ever read one of J.D.Power’s Initial Quality and Vehicle Dependability studies, you may have noticed that Tesla is never officially ranked.

You see, J.D. Power determines scores for each automaker after getting lists of owners from IHS and Experian. J.D. Power then surveys these customers directly and in 35 U.S. states, can do this without an automaker’s permission. In the remaining 15 states, carmakers need to give J.D. Power their permission to survey owners. Every brand does this, except Tesla.

Interestingly, these 15 states are among Tesla’s most important and forces J.D. Power to rely on the information it gets from owners from 35 states and uses calculations based on how premium buyers tend to respond in the 15 states where data isn’t available. Tesla ranked 31st of 33 brands in this year’s Initial Quality Study and in the Vehicle Dependability Study, was ranked 30th out of 33.

Read More: Lexus Tops J.D. Power’s Dependability Study, Tesla (Unofficially) 30th Of 33

Included in the 15 states where J.D. Power can’t survey owners are California, New York, Pennsylvania, Illinois, Washington, Arizona, Maryland, Oregon, Nevada, Kansas, Hawaii, New Hampshire, Montana, South Dakota, and Alaska. Through January–September 2021, these states accounted for 134,000 Tesla registrations, more than half of the nationwide total of 230,855. Of these states, California is Tesla’s most important, accounting for 83,448 registrations in the first nine months of the year.

Speaking with Auto News, J.D. Power’s veteran vice president of automotive quality, Dave Sargent, noted that the rest of the industry is left asking why Tesla is left off the company’s charts, although he says Tesla has every right to stay on the sidelines.

“If people in California were exactly like people in Texas or Florida, that would be fine,” Sargent added. “But they’re not.”