Guns per person has gone up significantly. A wild guess might be 20-40%, but exact estimates are difficult. Sales are tracked and have gone way up, which is the starting point for estimating change in guns per person, but difficulty in estimating and combining all the factors makes it difficult to integrate.

(Most states don't track ownership, background checks aren't 1:1 with guns, gun purchase stats depending on how they're reported might include used guns, guns manufactured aren't necessarily going to civilians, and of course some guns are permanently lost or destroyed, or taken out of the country.)