I'm with Harriet here, there are lots of ways in which the employment prospects of nannies can be predicted to suffer in a credit crunch
eg supply and demand
employers needing to shave costs so preferring the inexperienced/unqualified (ie cheaper)
nannies having to take shares with larger numbers of children
lower tolerance of tantrums about putting employers coffee cup in the dishwasher
etc
etc
Surprisingly if one person earns 100000 then take home is 64,500, however since this couple have a nanny if both earn 50K then take home is 70,198 and if it is a 70:30 split then total is 68,913 (all figures approx.) I find those figures so surprising!
Nanny on £10/hr (funnily enough what the last one to reply to me wanted) will cost approx 39,052 (don't forget employers NICS navyeyelash)
However in your sums you are forgetting housing costs to buy a very average place round here 3 bed terrace, outside zn 1/2 no garden average condition on a repayment mortgage at 6.3% at CURRENT asking prices would cost over 53,000 a year (disclaimer am not in the process of doing this)
I think there has been a lot of ready cash floating around in the UK and nannies have been a big beneficiary of this, it will change, allready I see more people advertising for longer and I think more offering to do shares and part-time jobs.
I too am shocked (and have started threads) with the number of nannies working for cash in hand credit crunch will also mean this will drop therefore wages will drop. Virtually all my replies are along the lines of this, another one recently couldn't tell me what gross wage her hourly rate translated into. Her boss paid all her tax/NI she said. I have so far resisted the temptation to say if you can't tell me/it isn't on your payslip it's probably not being paid!