What happened

Shares of Tesla (NASDAQ:TSLA) were hit hard on Thursday, falling as much as 5.8%. As of 1:33 p.m. EDT, the stock was down 5.3%. Though the stock's decline comes amid a broader market decline on Thursday (particularly for many growth stocks), news more specific to Tesla likely contributed to bearishness surrounding the stock as well. Specifically, General Motors' (NYSE:GM) automated driving system outranked Tesla's Autopilot in a Consumer Reports review.

So what

Market indices fell on Thursday on the heels of rising U.S. Treasury yields, which are at multiyear highs. At the time of this writing, the Nasdaq Composite Index was down just over 2%. Some investors might be paring gains on growth stocks with premium valuations, such as Tesla.

A red Model 3

Image source: Tesla.

Meanwhile, General Motors' Super Cruise beat out Tesla's Autopilot in the consumer product rating agency's first ranking of automated driving systems.

"Cadillac's Super Cruise ... was top-rated because our testing shows it does the best job of balancing high-tech capabilities with ensuring that the car is operated safely and that the driver is paying attention," wrote CR's Patrick Olsen.

Tesla's Autopilot came in second, followed by Nissan's ProPilot Assist.

Now what

With Autopilot hardware included as standard in every vehicle it sells, the technology is integral to Tesla's business. Safety aspects of Autopilot, such as emergency braking and collision avoidance, are automatically enabled for all Tesla vehicles. But customers have to pay extra to access convenience features.

While it's good to see Autopilot as one of CR's highest-rated driver-assist systems, investors have high expectations for Autopilot. After all, Musk believes the same hardware enabling Tesla's latest Autopilot technology will eventually be able to power a full self-driving mode.

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