NEW YORK (CNN/Money) -
Occupants of small cars and small and mid-sized SUVs are most likely to die in an auto accident, while those in large cars and minivans are the least likely, according to a study released Tuesday.
Real-world crash statistics indicate that vehicles that are heavy and have a low center of gravity are safest while lighter vehicles and those with a high center of gravity are most likely to produce a fatality in an accident, according to the Insurance Institute for Highway Safety, which compiled the results using the number of deaths in actual vehicle crashes.
However, the study noted some exceptions. It found that heavier sports cars generally had a higher rate of death than lighter ones.
It also found that light pickups generally had lower rates of fatalities than cars or SUVs weighing about the same. The report's authors speculated the discrepancy was probably due to a differences in the driving habits of those driving lighter trucks.
While they could adjust for the differences between male and female drivers (female drivers are safer), they could not control other demographic factors that influence the death rate, the Institute said.
"Obviously, a Pontiac Firebird is generally going to be driven in a much different way than a Honda minivan," said IIHS spokesman Russ Rader.
Overall, the average death rate has declined to 87 deaths per one million vehicle models on the road from over 100 deaths in the 1980s, Raders said, despite far more hours per year spent behind the wheel.
He credited the improvement to better auto design, the instillation of airbags in new models and a rise in seatbelt use.
He also said older designs were one reason why nine of the 14 vehicles with the highest death rate were American while only three on the list of lowest fatalities were from the Big Three.
"Many of the U.S. companies have not replaced their designs as quickly as the overseas makers," he said.
The report noted that most deaths in big cars or minivans involved another vehicle, while most fatalities in SUVs were single vehicle or roll-over accidents.
It also noted differences within certain classes of vehicle. Consider the Infiniti G20's rate of 46 deaths per million registered years, which was much lower than rates for other small four-door cars, like the Chevrolet Cavalier's 162 per million or the Pontiac Sunfire's 160.
The same was true for SUVs. The Toyota 4Runner had only 12 driver deaths per million registered years during 2000- 03. This compares with 134 deaths per million for the two-door Ford Explorer and 119 per million for the Land Rover Discovery Series II.
IIHS said this information suggested engineering improvements, like stability control systems on the 4Runner, played a big part in improving the vehicle's safety.
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