The Wall Street Journal, NY Crime blog, January 25, 2011 by Sean Gardiner
http://blogs.wsj.com/metropolis/2011/01/25/checking-the-stats-how-to-verify-nypd-data/
Zimring said his research found that over the past 20 years, New York City’s crime rate reduction is twice the national average and has lasted twice as long. And what is especially impressive about that crime drop is that since 1990 the number of people police locked up from New York City has declined by 28% while nationally the incarceration figure has gone up 65%.