Here's an article that challenges the claim (from 2013, but same arguments apply).
http://smallestminority.blogspot.com/2013/05/declining-gun-ownership.htmlThe same author writes this a couple of days ago: "Yes, the General Social Survey says a smaller percentage of households contain guns than at some time in the past. However, Gallup says gun ownership is up. Either way, the total number of households has increased over time, resulting in the TOTAL NUMBER OF HOUSEHOLDS CONTAINING GUNS INCREASING, so there are MORE guns in MORE hands than ever before - the exact opposite of the WaPo headline ["America has more guns in fewer hands than ever before"]."
Also, the number of guns "owned" by women has increased dramatically in the past several years. Most reports assert that women are the fasted growing demographic of new gun owners, new firearm training class members, new CCW holders, and new firearm sports competitors,
So if the male and female members of a "household" now BOTH are firearm owners, whereas in the past only the male was an owner, there are
twice as many firearm owners in that household, but it is only counted as ONE household. See the problem with the math and the terminology and parameters (deliberately selected to give a particular impression?)?
I personally believe it's likely the reluctance of firearm owners to reveal their ownership to a stranger that skews the results. There is research that validates this view.
A woman doing research for an article on learning to shoot guns: "So anathema are guns among my friends that when one learned I was doing this piece, he opened his wallet, silently pulled out an NRA membership card, then (after I recovered from the sight) asked me not to spread it around lest his son be kicked out of nursery school."
http://www.slate.com/articles/life/human_guinea_pig/2004/11/guinea_get_your_gun.single.html