The following graphs give information about the fraction of each race in PvP over rating. There are two graphs for 2v2, 3v3, 5v5 and RBGs each.
The first graph depicts the percentage of each race depending on rating in each bracket.
The second graph shows the evolution of these percentages over time for all players above 2200 rating.
All those graphs are displayed separately for regions US and EU. Sorry for the mess ;o)