From the National Institute of Justice:
How Prevalent is Gun Violence in America?
In 2005, 11,346 persons were killed by firearm violence and 477,040 persons were victims of a crime committed with a firearm.
Most murders in the United States are committed with firearms, especially handguns.
In 2006, firearms were used in 68 percent of murders, 42 percent of robbery offenses and 22 percent of aggravated assaults nationwide. (Weapons data are not collected for forcible rapes. See table 19 "Violent Crime," from Crime in the United States, 2006.)
Homicides committed with firearms peaked in 1993 at 17,075, after which the figure steadily fell, leveling off in 1999 at 10,117. Gun-related homicides have increased slightly each year since 2002.Consistently, there are unique qualities in handguns which tend to make them the weapons of choice, particularly in impulse decisions - as in suicides, for example, and also these characteristics appeal more to certain demographics, but in all categories, guns are used more than any other kind of weapon. Decreasing guns and more strict regulation of guns tends to reduce these crimes rather than have the number remain static or increase with a different weapon replacing firearms.