A problem with the underlying data IS ...
.. it is based on "polls" ...... Here's my point.
"Knock, knock! Hi, I'm Joe Smuck with the National Syndicate Polling Institute doing a survey on how many people have firearms in their homes. Do you have a firearm in your home?"
Peson at door: "Fuck you!" and slams door.
Pollster: I'll mark that down as a "NO"!