Burglaries in Paradise Valley, Arizona, fell from 195 in 2011 to 55 in 2014.

At a cost of $20,000 per license plate reader, 15 going up to start, and 55 total burglaries… that’s about 3 1/2 burglaries per reader. So, it’s not about reducing the 55 burglaries at all, is it?

Source: Arizona town’s new license plate readers aim to reduce already-rare burglaries | Ars Technica