It looks very complete to me- some of the very first clubs included. I checked for my area (upstate NY) and it looks complete. It links you to the archive to check if shows for that venue are available.
"Do not write so that you can be understood, write so that you cannot be misunderstood." -Epictetus
First show: 8/16/69 (Woodstock)
Last show: 3/19/95 (Unbroken Chain breakout)