I can believe that less new homes are buying guns, but not that less homes have guns than say 10 years ago. Even if it were true I don't see how it could even reach a statistical relevance.
I would have to dig up the stats when I get home. What do you mean by statistical relevance? Do you mean if the change is statistically significant?
Basically it boiled down to that if you are going to own a gun you tend to own several. Fewer people as a percentage of population choose to own guns however.