What happened

Shares of online car-shopping service TrueCar (NASDAQ:TRUE) were down sharply on Tuesday, after the company posted a wider third-quarter loss and scaled back its full-year guidance.

As of noon EST, TrueCar's shares were trading at $11.10, down 32% from Monday's closing price.

The entrance to TrueCar's corporate offices in Santa Monica, California.

Image source: TrueCar.

So what

TrueCar's third-quarter result was a mixed bag. While the total number of vehicles purchased via its service rose 15% from the year-ago quarter, its average fee per sale dropped to $306 from $319. Likewise, while its total number of new-car dealer partners rose 16%, the average revenue realized by TrueCar per dealer fell 5% to $5,319.

The results were exacerbated by changes at TrueCar's most important referral partner, USAA, which revamped its website in ways that reduced the amount of traffic referred to TrueCar. CEO Chip Perry expressed optimism that the situation with USAA would improve, but it may not fully recover.

Now what

As a result of the changes at USAA, TrueCar also lowered its full-year guidance around sales and revenue. It still expects both to increase from 2016 levels, but it had previously guided to significantly higher results.

Things aren't looking as rosy for TrueCar as they were in the first half of 2017.

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