For most of the selloff and recovery, I have mentioned that my favorite market analogy to our current situation has been 1973-74, which had a 55% collapse and 74% snapback rally.
However, as this market has continued to power higher, it has left 1973 behind, and is looking more and more like the Great Panic of 1907:
1973-75 Market versus 2008-11
1907-09 Market versus 2008-11
All charts courtesy of The Chart Store