What is the average hourly rate for indoor cycling/ spinning instructors?

Thanks Karin, Christina and Alice for your answers. I recently asked for an increase from $20.00 per class to $27.00. I teach the early bird class on Monday and Wednesday mornings 6am and the late evening class on Tuesday and Thursday at 8p. I found myself having to double back to teach from Tuesday 8p – Wednesday morning 6a. I’ve been doing this for about 8 months, my class participation is consistantly between 9-12. I was offered $25.00. Any suggestions?