baseline is 1500
http://wiki.warlight.net/index.php/Ladder_Ranks_and_Ratings#Run_your_own_Ladder_Simulations
here it shows you how to run your own ladder simulations...
one of the things it includes is a notepad showing the current ladder input.
note in the last section of this it says "offset 1500" base ELO is 0, in order to try to prevent there from being negative numbers shown, all players are effectively 'given' 1500 pts.