NEW YORK ( MainStreet) — U.S. car thefts have tumbled to around 700,000 a year from more than 1.6 million in 1991, but here are five cities where you still better remember to lock your vehicle's doors.

"People shouldn't be inordinately worried about vehicle theft, but you can't be stupid, either," says Frank Scafidi of the National Insurance Crime Bureau , which recently released its 30th annual Hot Spots list of metro areas with the highest auto-theft rates.

The NICB, which compiles statistics for the insurance industry, generates its annual list by analyzing an FBI database that police around the country use to report stolen vehicles. Metro areas at the top of this year's list had the highest number of auto thefts relative to population during 2013.

California cities far and away lead the pack, accounting for all five communities at the head of the rundown and nine of the top 10. The state's Central Valley region, an area hard hit in recent years by foreclosures and high unemployment, does particularly "well" on the list.

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Scafidi, who's based in Sacramento, says California has traditionally had a big problem with auto thefts — partly because the Golden State has America's largest number of both cars and people.

California's good weather also means cars tend to last longer there, giving the state a larger share of older vehicles that lack today's antitheft devices, Scafidi says. Add a large drug problem and easy access to Mexico for thieves who want to export stolen vehicles south of the border and you've got all of the ingredients for car-crook heaven.

"We're seeing less than half of the number of auto thefts that we were 20 years ago, and that's a heck of an improvement — unless you're one of the people whose car gets stolen," Scafidi says.

Read on to check out the communities the NICB found have America's highest per-capita vehicle-theft theft rate among the country's 380 major metropolitan areas.

All car-theft figures refer to 2013 FBI statistics for metropolitan areas as a whole, not just to incidents that occur within city limits. Jobless figures likewise refer to metro areas as a whole and reflect U.S. Labor Department non-seasonally-adjusted numbers for June, the most recent month with data available.

Per-capita property- and violent-crime statistics apply to just cities proper (not entire metro areas) and reflect a NeighborhoodScout.com analysis of 2012 FBI data, the latest year with final figures available.

Fifth-worst community for car thefts: Stockton/Lodi, Calif.
Be sure to take stock of your surroundings if you park in Stockton, as this struggling community some 80 miles northeast of San Francisco saw more than 4,000 auto thefts last year.