How to Survive a Zombie Apocalypse | Danger Room from Wired.com

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The police officer's potential for hitting his adversary during armed confrontation has increased over the years and stands at slightly over 25% of the rounds fired. An assailant's skill was 11% in 1979...

In 1992 the overall police hit potential was 17%. Where distances could be determined, the hit percentages at distances under 15 yards were:
 
Less than 3 yards ..... 28%
3 yards to 7 yards .... 11%
7 yards to 15 yards . 4.2%
 
It has been assumed that if a man can hit a target at 50 yards he can certainly do the same at three feet. That assumption is not borne out by the reports.

An attempt was made to relate an officer's ability to strike a target in a combat situation to his range qualification scores. After making over 200 such comparisons, no firm conclusion was reached...MORE