Everyone knows Aesop’s fable of the ant and the grasshopper: the ant worked hard all summer to provide for the winter ahead; the grasshopper did not and paid the price.

A paper by PricewaterhouseCoopers partner John Hawksworth suggests that this fable, combined with insights from recent developments in behavioural economics, can help to explain why people in the UK are not saving enough for their old age.

Put simply, the paper argues that the UK is a nation of too few ‘ants’ and too many ‘grasshoppers’. It also suggests that this has important implications for government policy on pensions and savings.

It draws on psychological research showing that, contrary to most standard economic models, people do not discount the future at a constant rate per period. Rather, the discount rate applied when comparing the current period with the next period is much higher than the discount rate applied when comparing two consecutive periods far in the future.

People are impatient in the short term, with a strong tendency to prefer instant gratification to even a short deferral of rewards. Moreover, this leads to a systematic tendency for people not to stick to their future plans: for example, they always intend to save for their retirement but never get around to doing this in practice. This is what the paper refers to as the ‘grasshopper effect’.

The paper illustrates the effects of this through a simple mathematical model where people have to choose whether to spend or save in three periods of their life: youth, middle age and old age. The analysis considers the savings behaviour in these circumstances of three types of people, who are identical in all relevant respects apart from the way in which they view the future:

The paper goes on to show, with reference also to a range of other academic research in recent years, how these illustrative results can be generalised. Excessive early retirement, for example, may be the result to some degree of a similar ‘grasshopper effect’. US studies suggest that the grasshopper effect could be to reduce the household savings rate by as much as 10%. The paper then draws a number of policy conclusions: