Why a 4-day week might not make many of us much happier

As people consider the future of work post-COVID, the debate about a potential 4-day week has built up some mometum. Sadly, life is more complicated than a simple choice between a “standard” and non-standard work week. In fact, there doesn’t really seem to be a standard work week — and this phenomenon predates COVID-19 by several years.

Since 1992 (date from which I have data from the ONS), roughly a quarter of all people working have been part time. Between 1992 to 2019, the hours worked by each part-timer on average have increased somewhat, from around 15 to 16 hours per week. At the same time, total weekly hours for full-time workers have declined a little, from 38 to 37 hours. In fact, we are already working a four-day week, on average: the weighted average work week was around 4.3 days at the end of 2019.

People talking about the 4-day week are, then, probably referring to the three quarters of workers who currently work full time. However, as you would expect, even among these people there is a distribution of hours worked. This can be seen in the first column of the chart above. Nearly 60% of people working full time do so for 35–40 hours per week — but the other 40% have different working hours, working either more or less than that.

So, if this distribution shifted down and everyone started working a little less, would they be more satisfied with their lives? Well, it depends — and the dynamics could be quite complicated. For example, as I suggested in a recent Tweet, if reducing hours (systematically, across a whole workforce) boosted productivity, so as to compensate for lost hours, people (and businesses) could well be better off. [Another complication would be that people’s satisfaction with something typically depends not just on its absolute level, but its level relative to some benchmark, such as their school friends.]

I haven’t conducted a dynamic analysis here, but the static data in the Understanding Society shown in the chart helps us, nevertheless, to ground this debate in some interesting facts and economics. As I’ve mentioned before, people’s overall satisfaction with life is quite influenced by both their satisfaction with their income and their satisfaction with the amount of leisure time they have (as well as their health and relationships, among other things).

Since working more hours typically results in more income, there’s a clear trade-off here. Economists normally assume that people make a broadly rational choice: they will work up to the point where — for the marginal hour — they would rather have the leisure than the money. (Obviously, this is further complicated by the impact that all kinds of taxes and benefits have on the marginal income from that marginal hour.) Intriguingly, the data in the chart seems to back up the idea of rationality.

We can see, in the 2nd and 3rd column, that (full-time) people working more hours have a significantly higher income, and are somewhat more satisfied with their income, than those working fewer hours. [The tiny difference in the 3rd column is another interesting phenomenon — see my other blog on people’s subjective feelings about their financial situation here.]

However, the same people with longer hours experience a compensating loss of satisfaction due to fewer leisure hours, as seen in the 4th column. In the last column, we see that people’s overall life satisfaction (on the basis of admittedly crude analysis) is remarkably neutral to total hours worked. [The same does not apply to unpaid work: people doing more housework and caring are somewhat less happy with their lives. Again, this is not an “all other things equal” analysis, so this statement needs to be taken for what it is: an observation about statistical patterns, not necessarily causation.]

Personally, I actually think there are many nuanced reasons why a 4-day week “as a societal norm” could be a positive thing — but that’s a topic for another blog, at another time. For now, I nevertheless wanted to share this somewhat more sceptical analysis to help ground more of the discussion in facts.