Because of the large quantity of long guns in the rural communities of Canada, it is next to impossible to actually know how many there are. BTW, most of the rural community did not register theirs when the long gun registry was put out, they just ignored it. Also, a lot of the numbers are legal gun owners which are counted as one gun, most have at least 2, and in a lot of cases more than this. The other thing is, unless you stole personal, private data from the Feds, then how exactly would these newspapers know how many guns there are? The bottom line is we do have lots of guns in Canada, but we don't run around like idiots with them, and we have good laws to keep things from getting out of hand.
Over the last 5 years of shootings in the U.S., gun ownership has jumped way over 300 million in total. As per how many per households, this changes drastically depending which state you are in.