It used to be said that life begins at 40, but happiness now does not begin until 54, according to a new report.
Almost one million 45 to 54-year-olds are unhappy with their lives - making their age group the most frustrated in the country, the study found.
Researchers for online bank first direct dubbed the age group the Baby Gloomers - Britons born between the mid-1950s and mid 1960s.
They found that 11.5 per cent of the 8.5 million people in that age group are discontented, while fewer than 40 per cent feel completely happy with life, compared to a national average of 48 per cent.
However at 54, more Britons describe themselves as "happy" and "content" than "stressed" and "self-conscious" for the first time, while 71 per cent of over 65s are content with their lot.
Money worries are the key concern of one in five (19 per cent) of Baby Gloomers - making them the most financially discontented of any generation.
Along with the prospect of later retirement, gloom factors for this generation include having to work longer to save for retirement, closure of final salary pension schemes plus soaring costs of parental care and children's education.
The research suggests that money has a less important role to play in happiness than many other factors.
The next generation up - called "Golden Baby Boomers" - place emphasis on travel.
Nearly one in 10 55 to 64-year-olds (8 per cent) plan to go on a trip for three or more months.
First direct head of marketing Paul Say said: "The first generation of Baby Boomers is known as the 'Golden Generation'; those who came a decade later appear less fortunate, facing work and financial pressures that seem to be weighing down on them particularly.
"Three-quarters are resigned to working far longer to fund their retirement, compared to just six in 10 of the general population.
"But looking to other generations, people are gaining satisfaction in their lives from much more than just money. Even in their late 50s and early 60s, Brits are undertaking a raft of changes to make their lives richer, more colourful and - ultimately - happier."
* The research was conducted online among a nationally representative sample of 1,000 Britons aged 16-plus in August.