Technically, the assault rifles in Switzerland are not privately owned. They are government property.
Perhaps that's why the numbers for Switzerland are skewed.
As for Afghanistan, first there is the difficulty in counting due to the unstable environment. Second, the numbers only refer to LEGAL gun ownership. And third, MOST Afghans do NOT have weapons. Hard to believe, but true...at least from my experience with 24 months in country. Just seems like everyone is armed and that's the way the media like to portray it. Cops and soldiers go home unarmed, which is why they are often targeted for kidnapping and murder.