Sorry to say but,
be careful with the interpretation of this graph.
500 play money tournaments is nothing, and the stat BB/won that you have chosen is meaningless for tournaments.
For tournaments, the stats of ROI(return of investment), and ITM(In the Money) are more meaningfull.
Here a report over my tournament hands, look at the bottom of the table, for cash games these stats would be real good 17.95 BB/100 hands.
But for tournaments, this says nothing. You don't see placements (Final table placements, middle placements ITM, late placements ITM, placements where you did not win anything) and winnings in relation to your investment(buy in) of the tournaments.