nanny cost for three children

[Limpetsmum]

we live in yorkshire. We currently have an excellent nanny and she looks after our two little kids. i'm expecting a third child and want her to come back to us when I go back to work after maternity leave.
We would love for to come back and will offer her a pay rise should she return to us.
What is the usual rate people pay for a nanny for three children outside of london please? We currently pay in the region of £8-9 (gross) for her to look after two kids.
I should mention all three kids will be at home (i.e. younger than school age when she returns to us)

Nannies do not get paid for more children, its part of the job.

A small rise though would no doubt be appreciated, as long as that did not mean a drop in salary once one child goes to school!

Have a look at what others jobs in the area are offering. You want to keep them, not want them to move on to another family, so check your salary is competitive.