Drivers in Buffalo are more likely to experience an accident than in other cities of upstate New York or other parts of the country on average, though not as much so as in New York City or Yonkers, according to a new study by insurer Allstate Corp.

The study found that the average driver in Buffalo will suffer a car collision every 8.5 years, making drivers here 17.5 percent more likely to experience an accident than the national average. Nationwide, the average driver has an accident every 10 years, according to Allstate data.

That ranked Buffalo 126th in driving safety out of the 197 largest U. S. cities served by Allstate. By contrast, Rochester drivers have an accident every 9.4 years, while in Syracuse it’s every 9.8 years. And while Rochester and Syracuse drivers got better, Buffalo drivers got worse, with accidents occurring more often than in 2005.

However, Buffalo is the third-best Northeastern city out of 15 metropolitan areas. Syracuse was first, followed by Buffalo and then Pittsburgh. Hartford, Conn., was last in the Northeast, and ranked 190 nationwide.

“We don’t want drivers in Buffalo to be discouraged by their ranking,” said Allstate spokeswoman Krista Conte. “Instead, we want the report to challenge drivers in Buffalo to make positive changes to their driving habits that will in turn make the city a safer place to live, work and raise families.”

The fifth annual “Allstate America’s Best Drivers Report” ranks the cities based on car collision frequency. The company’s actuaries analyzed company claims data over a two year period from January 2006 to December 2007, to ensure external factors like weather or road construction didn’t affect the results, and then computed a weighted average. The data reflects where drivers live, not where the crashes occurred.

The nation’s “safest” city, based on the data, is Sioux Falls, S. D., where crashes occur every 13.5 years, and drivers are 26.1 percent less likely to be in a crash than the average driver nationally. That was followed by Fort Collins, Colo.; Chattanooga, Tenn.; Cedar Rapids, Iowa; and Knoxville, Tenn.

Drivers in large cities with populations of more than 1 million are more likely to experience collisions. Phoenix was the safest of those, with collisions every 9.2 years, followed by San Diego and New York. By contrast, Philadelphia was the most dangerous big city, with crashes every 6.4 years and drivers 57.1 percent more likely than average to have an accident.

Among the 10 most improved cities — those that most improved the number of years between accidents — five were in Virginia.

Allstate is the nation’s No. 2 auto insurer, representing about 11.3 percent of all U. S. auto insurance policies. Nationwide, while car crashes have declined in recent years, fatalities still average about 40,000 a year.