Dividing the total number of patents by 182 years masks some of the realities. Namely, there are significantly more patent grants in the past decade compared to any other. For example, 2015 had 325,979 patent grants, compared to 2005 with 157,718. There's a pretty clear trend, see
https://www.uspto.gov/web/offices/ac/ido/oeip/taf/us_stat.ht....