California topped the list of states where the problem occurred during the three-year period. Texas was next on the list, followed by Florida, Michigan and Ohio.
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If you subtract the number of cars stolen because owners left keys inside, the NICB says overall vehicle thefts would have dropped to a nearly 50-year low in 2014.
The sad part, Wehrle said, is that "Stealing a vehicle is very difficult with today's anti-theft technology and leaving the keys in the vehicle is an open invitation for the opportunistic car thief."
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In all, 126,603 vehicles were reported stolen with the keys inside between 2012-2014. During the last year of that study, the total was 44,828, or 6.7 percent of all the vehicles snatched that year. That was up from 5.4 percent in 2012 and 6.0 percent in 2013, suggesting the problem is getting worse.