Try looking here too Trace, they calculate it higher but without the break down.

http://swz.salary.com/momsalarywizard/layoutscripts/mswl_newsearch.asp

I entered my friends Texan postcode since it is set for the USA  and based it on average times for this household with two children between 6 & 18 and it came up with a figure I was amazed at, you can even print a " pay cheque" or email the results.