So, why did this happen? All crime has fallen, nationally and especially in New York. But there has also been a big shift in the economics of auto theft: Stealing cars is harder than it used to be, less lucrative and more likely to land you in jail. As such, people have found other things to do.
The most important factor is a technological advance: engine immobilizer systems, adopted by manufacturers in the late 1990s and early 2000s. These make it essentially impossible to start a car without the ignition key, which contains a microchip uniquely programmed by the dealer to match the car. ...
You can see this in the pattern of thefts of America’s most stolen car, the Honda Accord. About 54,000 Accords were stolen in 2013, 84 percent of them from model years 1997 or earlier, according to data from the National Insurance Crime Bureau, a trade group for auto insurers and lenders. Not coincidentally, Accords started to be sold with immobilizers in the 1998 model year. The Honda Civic, America’s second-most stolen car, shows a similar pattern before and after it got immobilizer technology for model year 2001.
Old cars are easier to steal, and there are plenty of them still on the road. But there’s an obvious problem with stealing them: They’re not worth very much.
--Josh Barro, The Upshot, on criminals responding to incentives