Wow nice article, I was wondering if I was charging too much for my recent bid. Good to see other people are charging in that range.
Don't worry what other people are charging, worry what your clients are paying and that they are happy.
You might not want to scrape out the absolute maximum each client will pay for each job (at the least, it's a very difficult thing to actually determine, and makes for a bad client experience if you're negotiating too hard), but it's always good to have a sanity check that they're not happy merely because you're charging way below market rates for your talent.