Sometimes it's hard to keep up with evolving government regulations.

The 2014 Toyota Prius hybrid has just been downgraded from five stars to four under the Federal New Car Assessment Program (NCAP) safety rating system, but not because Toyota did anything to change it.

Under a new set of crash tests conducted by the National Highway Traffic Safety Administration (NHTSA) last month on a 2014 model, the Prius earned a four-star rating in the frontal barrier test.

That kept its frontal score at four stars--the same as before--but lowered its Overall score from five stars to four.

The last time this test was conducted on a Prius was February 2011, using a 2011 model. Those results were applied to 2012 and 2013 models as well.

The Federal frontal test involves running the car into a fixed barrier at 35 mph with an average-sized adult dummy in the driver's seat.

The star rating is based on force measurements--which correspond to a certain likelihood of injury--at the head, neck, chest, and legs.

The 2014 Prius retains its five-star rating in all Federal side crash tests, including the side barrier test (for driver and passenger) and the side pole test--which simulates a collision with a utility pole or tree.

It's also worth noting that the Prius was last redesigned for 2010, but it still remains fairly competitive in terms of safety in 2014. A completely redesigned Prius is expected for 2015.

In fact, the 2014 Liftback model is essentially identical to the 2013 model that scored five stars in the old frontal barrier test.

It also retains that model's $24,025 base price and EPA-rated fuel economy of 50 mpg combined (51 mpg city, 48 mpg highway).


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