Motion Graphics Rate Increase

Hi Guys,

I am in the Los Angeles market, and have a freelance client who has been pretty consistent with work the last 6 months. By consistent I mean 2-3 weeks of work a month. I enjoy working there, and it's close by to home. I think my rate is fair relative to my experience, but have been told by some fellow motion graphics artists that I could be charging more for my work. Some have even suggested $15.00 per hour more. I have been charging my current rate for about 10 months. Any advice on raising my rate and when on a favored client?

I've been doing MoGraph for 3 years and finished certified training in 2006.

Thanks!

www.timbowen.com