Well, that's a bit of a screw up, and I like to do things right. Unfortunately, I can't come up with more hard data on gun ownership for another year. If you know where I can find it, please let me know.
Here is data from 2007, for gun related deaths. The plot is data by state for 2007 vs 2006. As you can see, for what it's worth, there's not much drift over the span of a year. Gun ownership is a cultural phenomenon, and one of the indicators of how divided we are as a nation, and from the rest of the world. I doubt if this number changed a great deal between 2001 and 2006.
Here is a look at how the U.S. stacks up against the civilized world on gun deaths. The aggregate U.S number is 10.2.
I've eyeballed a best-fit line through the other countries' data, and circled the U.S data point.
Doesn't look like we are on the same planet.