The second-richest county in the nation is Falls Church City, Va.

FORBES: America's Richest Counties

Cyril Falls, 53, who is a teacher at Bangor Academy, County Down, said he thought it was OK to throw the apple core because it is biodegradable.

BBC: Apple core litter fine angers County Down driver

The only way to answer the questions about why crime falls, he says, would be to build a wall around each county in the UK, and then change the conditions to establish the influencing factors.

BBC: What's the price of DVD players got to do with crime?