What is a good BB/100 number

Whats up everyone up too out there. Right now I am grinding out a 10000 hand challenge at 4nl and the goal is to make a profit. Right now I am winning at about 6.28 BB/100. Even though in the last 4 profitable sessions I have had at least 19 BB/100 on the last 4 sessions multi tabling. What I am wanting to know is what is a good number for BB/100. Give me your opinion and why.
Keep working to the top everyone.

On some forums I have read that 9 BB/100 is very good.