A finance industry analysis revealed the most speed-prone demographics that present vulnerabilities to higher insurance premiums.

The LendingTree report indicates Portland, Ore. Is the most speed-prone of the biggest 50 U.S. cities, as measured by the number of speed-related incidents per 1,000 drivers. Portland drivers had about 12 incidents per 1,000.

The North Carolina-based online lending marketplace doesn’t use the term “crash” or “accident” in the report, so the statistic likely includes citations for speeding without a collision.

Not surprisingly given their youth, the study found Generation Z drivers the most likely to be involved in speed-related incidents, also with about 12 per 1,000 drivers, easily surpassing millennials, who have about seven per 1,000. Baby boomers had the lowest rate at three per 1,000.

The distinction can bring painful repercussions. LendingTree says speeding incidents in the biggest cities make speeders’ average annual insurance premiums about $600 higher.

More important, it’s risky. “Speeding is one of the leading factors in fatal traffic collisions,” said LendingTree auto insurance expert Rob Bhatt. “We could save thousands of lives each year if speeders slowed down.”

Broken down by brand, Subaru drivers are oddly the fastest, according to the report, with about eight incidents per 1,000 drivers, followed closely by BMW drivers, at seven per 1,000, and Infiniti drivers at about the same rate.

At the more specific model level, Honda Civic drivers had the highest incident rate at nine per 1,000, in a virtual tie with Volkswagen Jetta and Chevrolet Camaro drivers.

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