From this piece by Geoffrey R. Stone of the University of Chicago: "If the United States had the same
gun murder rate
as England or Canada, approximately 8,500 American men, women and
children who were slaughtered by gunfire in 2011 might still be alive
today. If the United States had the same gun murder rate as England
since 2000, 100,000 murdered American men, women and children might
still be alive today."
Guns Don't Kill by Geoffrey R. Stone