You have a cite for that?
Sure: http://www.gunpolicy.org/firearms/region/district-of-columbia
Proportion of Adults Living in a Home With a Gun
ChartIn the District of Columbia, the percentage of adults living in a household with a firearm is reported to be
2002: 5.2%1
2001: 3.8%2
I had a friend at GSS a few years back and though they don't publish the full state level one, their internals show DC gun ownership to be under 3%. The gun control researchers call GSS the "gold standard." Everyone knows the number of gun owners is going up, and simply more people own guns for self defense, which is inherent private, compared to hunting, and more people take training that says tell no stranger. so of course self reported gun ownership is declining. I would not tell some pimple faced kid knocking on my door with a form that has my address on it (GSS method) and recording whether there is a gun at home!
GSS: 30% and falling the past 20 years
Gallup (more anonymity confidences): 38% and falling the past 20 years
NRA approvals: 58% and rising the past 20 years
Persons who say owning a gun at home makes their family safer Gallup: 63% and rising the past 20 years
Those last two are likely the gun ownership rates. On confidential matters those kind of indirect questions are proven by the science to be more accurate than direct questions.
You have to realize how this works, instead of normal science, the gun control academics work from their needed results (proving for example that "less Americans own guns", "more guns = more crime", "more guns = more murder", more guns = more suicide) and choose the ownership rate from whatever rate estimating method supports their thesis.
so for suicide studies they pick a low number for ownership, since DC has low suicide. for homicide they pick a high number of gun ownership since DC has high homicide.
For race distribution they pick GSS because African Americans generally refuse GSS questions more often, so as to "prove" that whites own guns ate 2.3 times the rate.
For "gun violence" they actually take the CDC "risk assessment" number on gun violence events and extrapolate that to estimate gun ownership rates by state --which is the most mendacious self fulfilling idiocy.