Most of the work on the costs of children has been done in the context of discovering how much is "enough" to raise a child. The question has not been how much can you spend - which is as infinite as mummy and daddy's wallets - but how much must you spend, which can be very little, depending on whether the DSS or someone a little more generous is the one doing the sums.
Nina Oldfield was responsible for a major study for the Child Poverty Action Group in the early Nineties. This took a "basket" of goods and services to assess two budget standards for children: a modest-but-adequate standard, which represented the costs of the average child, and a low- cost standard, which represented the bare necessities. The conclusion was that a child in a two-child family of modest income would cost its parents just under pounds 60 a week to raise. The more stringent budget would come in at pounds 30.37.
By the end of the decade, Nina Oldfield says, costs have rocketed even higher. A four-year-old in a two-child family is likely to cost at least pounds 50 a week, a 10-year-old girl pounds 56 a week (boys are more expensive!), a 16-year-old girl pounds 73, and a 16-year-old boy pounds 75 - just under pounds 4,000 a year. These calculations leave out any child-care the parents would have to pay for to allow them to go to work. That can account for pounds 100 a week for a child-minder, or pounds 180 or more per week for a private nursery.
Of course, these are theoretical budgets for people on average incomes. It hardly needs to be said that they outstrip what the poorest families receive when they are on income support: in spite of recent increases the allowance for a child under 11 stands at pounds 20.20 a week and for a teenager at pounds 25.90, with a family premium for parents of pounds 13.90 a week. And the figures undoubtedly under-estimate what many middle-class families spend on their children as a matter of course.
What parents actually spend comes in at much the same sort of average figure, according to the authors of Small Fortunes, a survey for the Joseph Rowntree Foundation. This concluded that average spending on a child comes to the massive total of pounds 50,396 between birth and the age of 17, or pounds 57 a week.
Where does the money go? A great deal - more than pounds 16,000 of the total - goes on food. Almost pounds 800 goes on nappies for the average baby, and almost pounds 4,000 on clothes, with the proportion of spending actually decreasing as children get older, presumably because they do not grow so fast. Another pounds 4,000 or so will be gobbled up by Christmas presents over the years, and rather more than that on birthday presents.
And if new parents think that their baby is expensive, they should be aware that spending on children only rises at time goes by. The hulking teenager really is more of a drain on the family finances than the toddler.
There are also serious questions already being asked about what constitutes a necessity for the Millennium generation about to be born. When the Joseph Rowntree researchers asked mothers what they spent on their children it was clear that their priorities were slightly different from those of the experts who tend to be drafted in to assess appropriate budgets. Mothers' priorities were enabling their children to participate in whatever their peers were doing. And many made sacrifices in other areas of expenditure to enable their children to be included.
Social exclusion for children is not simply a question of not getting enough to eat, but not being able to take part in school activities and wear acceptable clothes. Soon it may also be about having a computer at home to enable children to keep up in the IT generation. And as more children aim to go to university, it may also be about being able to afford the fees and living costs that an extended education implies.
Bob Wilkinson, Regional Sales Director of Forester Life, suggests that before starting a family, young couples should spend a little time on financial planning. He says that even if they are not anticipating the large investment in private school fees which some families commit themselves to, there are still educational expenses through the school years which can be dealt with by savings plans, as can the costs of a university education.
"Four years at university can cost up to pounds 20,000, and parents end up contributing in spite of the loan scheme," he says. "Parents really need to take professional advice on the costs of bringing up children these days, and look at the sort of flexible savings schemes which have been developed to meet this particular need."
At their 17th birthday, a child will have cost on average pounds 50,000 to bring up
Child benefit meets approximately one fifth of the cost of a child
Ten per cent of spending on children comes from grandparents and other relatives
One in 10 children go without three or more items which parents generally consider are necessities because their parents can't afford them
Spending on children increases as they get older
Source - Small Fortunes, the Joseph Rowntree Foundation