A good way to have a great annual return in year y+1 is to have a 21% decline during December of year y.
2017: +21.83%
2018: -04.38%
2019: +32%
(All numbers are total return, the 2019 source didn't have fractions of a %)
That's not a bad four years' return.
(Yes, December 2018 had a big decline -- but the first 11 months of the year were pretty good, and we ended only 4.38% off even with the 21% decline in the last month)
No wonder the world has gone to hell!