If you are stuck for a topic of conversation next time you are in a London taxi, you might like to bring up rising life expectancy. The company that produces many of the distinctive black cabs, Manganese Bronze Holdings, saw a £1.7m (€2.1m) pensions payment wiped out last year thanks to predictions that its retired cab manufacturers will live – and draw pensions – for longer.

The problem posed by longevity becomes worse each time a financial director looks at it. When UK telecoms company Vodafone said last month its chief executive, Arun Sarin, was to step down in July, aged 53, it was estimating that its male workers would live to 87. This was three years longer than it had estimated a year earlier. Two years ago, it had not considered the estimates worth publishing.