A stronger economy has slightly increased your risk of dying in a late-model vehicle, according to a new study from the Insurance Institute for Highway Safety.

Experts say as unemployment falls, vehicle miles traveled and crash deaths both increase.

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Size matters when it comes to car safety

This IIHS study found the overall rate of driver deaths for 2014 and equivalent earlier models is 30 per million registered vehicles, up from 28 for 2011 models.

The new driver death rates are based on deaths that occurred from 2012 through 2015.

“Vehicles continue to improve, performing better and better in crash tests,” says David Zuby, IIHS executive vice president and chief research officer. “The latest driver death rates show there is a limit to how much these changes can accomplish without other kinds of efforts.”

Smaller cars are the deadliest on the road, the report found. The worst was the Hyundai Accent, with 104 driver deaths per million registered vehicles.

These vehicles have the highest driver death rates, according to IIHS:

1. Hyundai Accent sedan
2. Kia Rio sedan
3. Scion tC
4. Chevrolet Spark
5. Nissan Versa
6. Ford Fiesta sedan
7. Kia Soul
8. Dodge Challenger
9. Nissan Titan Crew Cab short bed 4WD
10. Nissan Sentra
11. Ford Focus sedan
12. Chrysler 200
13. Hyundai Genesis coupe
14. Ford Fiesta
15. Hyundai Accent
16. Mitsubishi Lancer 2WD
17. Volkswagen Golf
18. Chevrolet Impala
19. Dodge Avenger 2WD
20. Ford Mustang convertible
21. Nissan Maxima

On the other hand, 11 vehicles had a driver death rate of zero for the four years analyzed. They include the Audi A6 4WD, Jeep Cherokee 4WD and Toyota Tacoma Double Cab long bed 4WD.

See the full list of vehicles with the highest and lowest driver death rates from IIHS.

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