Anonymous
About 35 an hour plus 3 weeks paid vacation.

oh, PP. it isn't nice to haze a new mother with such a crazy post. She won't know you're joking and may actually think she should pay such a ridiculous rate! Behave yourself!
OP, there are a lot of rate threads here you can search. You'll find a small subset who quote very low rates and a small subset who think nannies in your area should earn $20+/hr. the reality in your area for one child that age is between $15 and $17/hr. check with your neighbors, your local list serves, and get referrals from people you know who employ nannies. You'll find the vast majority in that range.
There are other things you need to consider when putting together a good package, like guaranteed hours, paid holidays (be very specific which ones), paid vacation (usually two weeks, one your choice and one hers) and paid sick days (or PTO). If you require her to use her car on the job, you should reimburse her at the IRS rate for all driving on the job (but not her commute).
There are additional perks you can offer that will be attractive to candidates. You can consider a health insurance contribution, or an extra week of vacation, or a specific bonus structure, transit allowance, or meals provided by you when she is on the clock. None of these are standard, but all will be nice pluses.
Make sure you pay legally on the books, require clean driving record and clean criminal background check, and require certifications in first aid and CPR.
Be very clear about your expectations regarding everything from texting to what she will do during nap time.
The more requirements you have, the more likely you will pay at the higher end. But unless you need a nanny specializing in medically sensitive children and has a nursing degree, there is no reason to pay more than $18/hr at the high end.