I occasionally check usage (I use Aperture Inspector for the Mac), but not annually. I did just have a look for 2016 (like you, I base stats on the RAW files that I've processed although I'm current except for a few on the cards in 1D X). I was actually a bit surprised by the results.

For cameras, my usage was 66% the 1D X and 34% the EOS M2. I used the little M2 much more than I though I would!

As for lenses, the top three were used for 3/4 of my shots and were:
EF 70-200mm f/2.8L IS II USM – 33%
EF-M 11-22mm f/3.5-5.6 IS STM – 23%
EF 24-70mm f/2.8L II USM – 20%

The 24-70mm was typically #1 (it's still #1 for all time use, 17% of total shots), but this year the girls have been more active with indoor activities – swimming and gymnastics, and in late fall they added horseback riding (which in New England late fall/winter, is an indoor arena activity!).

This year, I only use the 600/4L IS II for a small fraction of shots (<1%), mainly lack of time to get out to birding locations (Brant, we should get together this winter!).

Definitely an interesting exercise. Thanks for sharing, Brant!