Very hard to get any accurate information.
Would you tell anyone that you own any or how many you own? Most people will not tell a stranger or someone “collecting”
information.
NICS checks, hunting license’s, etc. have been used but obviously have no accuracy as far as how many guns or gun owners there are.
Many articles regularly cite 300 million as the number of firearms in the United States, I believe that number is no where near the actual. I would say closer to a billion.
In Missouri one time they cited the number of hunting licenses or deer tags sold in regard to gun owners. That year out of the 30-40 gun owners I personally know not one of them got a dear tag.
I wouldn’t be surprised if your 1B estimate is low. How many recorded sales has there been in the past 8 years? I’m thinking over the past 4 years each year was record breaker and right now there is a renewed buying frenzy. When Trump wins there just might be some bargains to be had.