A HEADLINE in Tuesday's paper (this one, alas) caught my eye: Woman 'can be head of house'. Those inverted commas, meant to signal that the paper distanced itself from this astounding discovery, didn't fool me. They wouldn't put commas round Man 'can be head of house', would they? Everyone takes that for granted.

Well, I've been head of house for nearly 30 years now, so this recognition looks a touch belated to me. When my young husband scarpered with his secretary (to, as it happens, her house), I took on the children, mortgage, bills, insurance, rates, fees and every other expense down to goldfish food, and coped with them single-handed out of one salary - my own. As do thousands of women: today, more probably millions.

A 1991 government report called Family Spending documents with admirable thoroughness the various permutations of British households. It lists, under households comprising one man, one woman, two children - the popular image of a family - just one in 10 households. Households headed by one woman with two or more children amounted to 2 per cent. Nearly 28 per cent of all households consisted of one person living alone - no indication of sex, but presumably as likely to be female as male.

Crudely interpreted (I'm no statistician, but I do have vestiges of common sense) we could assume that at least 15 per cent of all British households are headed by a woman, be she single-parent mother, childless or widowed.

Within my own immediate family circle - not an unduly large or unusual one - five households are headed by a woman, in three cases a woman earning more than her partner. My mother, recently widowed, lives alone. My daughter, a student, also lives alone (by choice, I find myself adding defensively). My sister works; her partner does not. My son's partner earns at least twice as much as he does. I, too, earn more than my partner.

Here is the crucial point. The last three, all main or only breadwinners in our households, don't show up in the statistics at all because they scarcely allow for the possibility of our existence. The assumption is that the breadwinner and higher earner is male. Household income is listed in most government and social analyses, but whether it derives from the male or female members of the household is not differentiated. No survey that I have been able to track down has been undertaken specifically to examine the contribution of high-earning women or households headed by a woman.

A host of misapprehensions result from this yawning gap in the figures. Major consumer purchases are targeted at men. Property, cars, computers, insurance, pensions - all these are mostly advertised on the assumption that the hand that signs the cheque will be male.

There may be some winsome female participation in the decision ('Let's do one in pink,' you can imagine the marketing chaps saying. 'It'll appeal to the wives.'). But the big serious factors, like terms and interest and megabytes of RAM and rustproofability and seconds from 0- 60 mph, are all based on the presumed workings of the male mind.

Turning to the ninth, and most recent, British Social Attitudes report - an admirably open-minded analysis of the changing way of life in Britain by the independent institute, Social and Community Planning Research - my eye is caught by the chapter entitled 'Men and women at work and at home'.

It begins by pointing out that 'the single long-term trend probably most responsible for changing the roles of men and women is the marked increase in women in the labour market'. Money is power, as we always suspected. Nevertheless, 62 per cent of women believed job opportunities were worse for women than for men. The fact that this figure was only 51 per cent in 1984 probably reflects the fact that in a recession, when jobs are hard to come by, women may be expected to leave the labour market clear for men.

Then there is a section called 'Gender roles'. It points out that, even when they do have jobs, women are less likely - not 'unlikely', let alone 'never' - to be found in higher managerial and administrative categories. Yet 10 per cent of women working full-time fall into these categories, with another 13 per cent in the professions. Add self-employed women running their own businesses, and these statistics represent a significant percentage of working women earning high salaries. Yet, apart from glossy advertisements for health hydros and business suits, they are virtually ignored.

We are invisible. It is taken for granted that women's share in bringing home the money, making economic decisions and paying for household items is secondary.

I am not being sarcastic. Asked by researchers for British Social Attitudes to respond to the statement, 'A husband's job is to earn the money; a wife's job is to look after the home and family', 35 per cent of all men agreed or strongly agreed. And this is 30 years after Betty Friedan issued her call to housewives, The Feminist Mystique. She described how, as a young married woman, she had accepted the all-pervading vision of the contented housewife, bread in the oven (bun too, more than likely), sheets in the airing cupboard, cat in its basket, all's right with the world.

She set out to interview such women and ask how they did it, since she herself was signally failing to find satisfaction in the role. And lo, the contented housewife proved to be a rarity, almost a myth, and centuries of male assumptions and female compliance were routed.

Yet here we are today, in what is sometimes called the post-feminist era, and still more than a third of men think that's where women belong. There is some consolation to be found in the fact that of men in the 18-34 age group, the young husbands and partners of today and tomorrow), 65 per cent disagree or strongly disagree, while of those men whose formative years coincided with the era of feminism, the 45-54 year olds, 54 per cent do too.

What will be the consequence of this? The existence of high-earning, economically powerful women will register more strongly in the minds of manufacturers, advertisers and employers. Their views and preferences will be taken into account.

No longer will the heroine of the Gold Blend ad be portrayed as a career woman in search of a husband to sweep her away from all that exhausting professional effort, those international flights, those conferences, meetings, files brought home. He may henceforth be categorised as her dependant. A small step for man, a giant leap for womankind.