Despite signs of decline in gun ownership, the US still has a huge number of private guns. In 2012, Americans owned an estimated 270 million guns, almost 42 percent of the total number of civilian-owned guns on the entire planet:

In developed countries, there is a strong correlation between the number of guns and incidences of gun violence. In 2012, the US, which has the most guns per capita, also had the most firearm-related homicides of developed countries. Japan, which has the lowest rate of gun ownership, had the least:

Looking at the entire world, countries in Central America like Honduras, El Salvador, or Mexico have the most gun homicides per capita. But among the developed countries, none gets even close to the US.

Note: The world crime figures cited above are collected by the UNODC through its annual crime survey and were compiled by the Guardian.