Win rate

[kstamps22]

I played 3/6 and 6/12 for a year and a half and built my bankroll and have recently moved up to 15/30-20/40. I play almost exclusively live games at a casino. Since I moved up I have been winning about $2,000 a week for about 1 1/2 months playing an average of 40hrs a week sometimes more. Is it possible to keep this up or am I running unusually good? What is a good average win rate at this level?
Thanks
Kevin