From the ArcaMax Publishing, Jokes Newsletter:
http://www.arcamax.com/news/jokes/s-371097-126249
Three statisticians went out hunting, and came across a large deer.
The first statistician fired, but missed, by a meter to the left. The
second statistician fired, but also missed, by a meter to the right.
The third statistician didn't fire, but shouted in triumph, "On the
average we got it!"