M.M.
Rates depend on many factors, does she speak English? Is she college educated? How much experience does she have? Nannies make anywhere from $300/week to $1000/wk & even more in Los Angeles. If you love her and want to keep her, show her that you value her & give her a raise. If you really can't afford it, talk to her & explain. She will appreciate it. I was a professional nanny for 8 years. I've helped many friends find good nanny positions. If she is any good & has experience she can make much more than what you are paying her.