A more interesting number for the gun control debate is the percentage of households with guns. That number in the U.S. has been declining -- pdf, but it is still very high in comparison with other developed nations.

However, exact comparisons of gun ownership rates internationally are tricky. The data is often sparse or non-uniform in the way it is collected. The most consistent comparisons I could find -- and I'd love to see more recent data -- were from the 1989 and 1992 International Crime Surveys. The numbers are reported in this paper on gun ownership, homicide, and suicide -- pdf. These data are old, but in 1989, about 48% of U.S. households had a firearm of some kind, compared with 29% of Canadian households. However, the numbers for handguns specifically were very different. In 1989, only 5% of Canadian households had a handgun, compared with 28% of U.S. households.