People spend on average one and a half times as much time in unpaid as in paid work, with women putting in nearly twice as much time as men unpaid. Depending on whether this effort is valued at average pay rates or at the low rates typical of the catering and childcare industries, it is worth somewhere between pounds 341bn and pounds 739bn, or between 56 per cent and 122 per cent of conventionally measured national output.
Catering in the home by itself forms the equivalent of a pounds 140bn a year industry, with a wage bill that would be around pounds 60bn if the home cooks were paid the same average hourly wage as employees in the commercial catering sector.
The figures are derived from the results of a survey of how 2,000 adults, including students and pensioners, divided their time over a full week.
Out of a total of 1,440 minutes in a day, sleep and rest absorb more than a third at 536 minutes, while leisure and eating account for 396 minutes.
Paid work plus commuting time takes 214 minutes, compared to 280 minutes for unpaid work. Domestic activities such as childcare, cleaning and cooking make up the bulk of this, although the totals also include DIY, time spent in educational activities and voluntary work. Men and women reported very different patterns of activity. Men on average spend longer than women in paid work each day, at 212 versus 127 minutes. But women put in 295 minutes of unpaid domestic work to men's 155 minutes.
The biggest discrepancy shows up in laundry and mending, where women's effort amounts to eight times more than men's. Slovenly males spend only three minutes a day on the care of clothing.
Men outdo women on only two fronts. They spend 22 minutes a day on DIY versus 6 minutes for women. Men's 33 minutes on "self-improvement" - mainly education - exceeds women's 21 minutes.
The fact that the figures are averaged over weekends and holidays as well as weekdays means that they do not paint a portrait of anybody's typical day. Even so, some of the discrepancies in the breakdown between men and women are surprising.
For example, it suggests that men sleep and rest for six minutes a day less than women. But, as Henry Neuberger, of the Office for National Statistics, pointed out: "It is a self- reported survey." Perhaps we must assume that some men record lying in bed as self- improvement rather than rest.
In carrying out the time-use survey, the ONS has followed an example set by about half the other EU countries. It is using the results to create a household "satellite" to the formal national accounts.
This first satellite for unpaid work shows that even on the smallest figures it far exceeds the total value of Britain's industrial production. Mr Neuberger said: "You can get a very distorted picture of trends if you fail to take account of the production that goes on in households."