As an hour-long exercise class in Cromer’s parish hall culminates in a triumphant ribbon routine, irrepressible instructor Annamarie Sterne addresses the group. “Has anyone got a knot?” One or two raise their hands, before another baffled attendee discovers she’s managed to swirl two knots into her ribbon. “How did that happen?!” she laughs.

The 40-strong class overwhelmingly made up of women over 65 – the oldest, Anne, 84, completed the entire routine – is a picture of health in older age. A few opt to exercise from a chair during the floor work, but everyone has put their all into the hour. “Their attitude is amazing,” says Sterne, who calls her class the “crème de la crème” of the north Norfolk town’s older population.

There should be little surprise at the demand for Sterne’s classes, and not just because of her infectious enthusiasm. One in three people in north Norfolk are now 65 or over, making it the oldest place in England and Wales in terms of the proportion of pension-age people.

Its leading status was revealed in new census data underlining what statisticians, economists and politicians have known for years: that Britain is ageing. There are now more people aged 65 and over in England and Wales than children aged under 15. The number of people aged over 64 has surged by 20% over the past decade in England and Wales, to 11.1 million people. Nearly one in five people are aged over 65.

The sweeping implications of this demographic revolution can scarcely be overestimated. From Tory pressure on Boris Johnson over tax and spend, to the crisis in ambulance waiting times, so many of the pressing issues of the day are being impacted by the large cohort of people who have worked their way into older age.

Despite years to plan, however, many experts are questioning whether the country has prepared properly for the economic, cultural and political changes this is driving.

The impact is uneven, both geographically and economically. Several of the women in Sterne’s fitness class tell a similar story of holidaying in seaside Cromer before retiring there. The fact that so many people have taken a similar decision has advantages. The women reel off a packed social calendar. Mondays, singing. Wednesdays, art. Friday evenings, drinks by the pier. The local WI has a waiting list.

Yet they are also aware that, as fit, able people with the means to support themselves, they are the lucky ones. “I’m perfectly OK, financially,” says Marg Hooper, 69. “But, my goodness, I feel for those that are not. It’s hard in that position.”

Sue Sansby, 75, agrees. “It’s geared to retired people here. And we can’t compare ourselves with a 75-year-old living in a high-rise. If you’re a pensioner with a private pension as well, you’re probably OK. Everybody’s not in that position.”

While a strong community has developed in Cromer, the concentration of older people highlights the pressures on health, housing and social care seen nationally. “North Norfolk is a wonderful place to live, and people move here for that reason,” said Tim Adams, leader of North Norfolk district council. “This trend is only going to continue for years. I’d question if we’ve prepared enough for that. I know of a lot of households that have unmet social care needs now. That leaves them reliant on charities, neighbours and family members. It’s putting a lot of strain on people. But people who work in social care also need housing. That’s another area where we really haven’t done enough.”

Aideen Young, of the Centre for Ageing Better, described the census figures as another wake-up call, showing the urgency needed to change attitudes to work, reach older people in poverty, make homes that are suitable for them to live in – and tackle a pervasive ageism that she says remains firmly in place. “In spite of the fact that we’ve known that this is happening, are we getting it right? No, we definitely don’t think so,” she said.

Britain lost a chance to be ahead of the game. As premier, David Cameron ordered a major study into all the impacts and implications of Britain’s ageing. With buy-in from Cameron, his policy guru Oliver Letwin and then cabinet secretary Jeremy Heywood, the Future of an Ageing Population report made sweeping recommendations on work, training, housing, health, transport, technology and care. There was just one problem: it was published within weeks of the 2016 EU referendum, and Whitehall has been fighting crises ever since.

“Potentially, prior to Brexit, we were going to be doing pretty well,” said Sarah Harper, professor of gerontology at Oxford university, who chaired the report’s expert group. “I think we would have been one of the leading countries in sorting this out. That has obviously passed and there are now huge problems. The fact that we can’t even get health and social care sorted out shows that we have dropped down the league in our ability to be able to tackle this.”

She added that Britain’s ageing process isn’t just about longer lives, but also a relative drop in younger workers. Birth rates are down and immigration is being reduced. “We knew we were going to be in a very tight labour market – this is not a surprise,” she said. “Brexit and the pandemic have made that so much worse for us.”

The consequences are being acutely felt in Westminster. The prime minister, whose premiership is already under siege, has been attacked by hawkish Tory MPs over the size of the state and his refusal to heed their calls to cut tax. However, David Willetts, the Tory peer who has studied demographic pressures for years, says the impact of our ageing population has driven the politics. “In 2017, we saw more people celebrating their 70th birthday than ever before in British history,” he said.

“This big cohort, who were hanging out in Carnaby Street in the 1960s and rioting in Grosvenor Square against the Vietnam war, are now all collecting their pensions and pushing up health spend and pension spend, even before you add in the increase in life expectancy.

“Margaret Thatcher was operating in an environment where she had a relatively small number reaching pension age. We had a bulge of workers with relatively few children and relatively few old people. And that is a very different environment for controlling public spending than the one we’ve got today.”

With the greater numbers, the divide between the haves and have-nots in later life is ever more stark. Willetts thinks something has to give. He believes the “triple lock” that sees the state pension rise by inflation, earnings or 2.5% – whichever is highest – is “an unsustainable ratchet pushing up pension income”.

He adds that the pension age may have to increase again, an issue being studied by an independent review for the Department for Work and Pensions. He believes those older people now struggling to find work and support themselves should be “a priority for focused public spending rather than the generality of pensioners”.

Given the labour shortages emerging across the economy after Brexit and the pandemic, it seems extraordinary that older workers should have difficulty securing work. Yet something strange is happening in the workplace. Over the past two years, the number of economically inactive people aged 50-64 has risen by 250,000 – a major reversal in the trend over the past decade. Covid appears to have hit older workers disproportionately, but many experts believe a persistent ageism also remains. Not enough employers have adjusted to the reality that more older workers are both needed and capable of doing the job, they say.

Andy Briggs, chief executive of the Phoenix Group pensions company and the government’s “business champion” for ageing society and older workers, pointed to research showing applications from older workers had far less chance of leading to an interview than younger applicants with similar capabilities for the job.

He also said older workers rule themselves out of jobs they could do – but added that there was action the government could take. “One in four over-50s have significant care responsibilities for an elderly relative,” he said. “And yet the vast majority of businesses don’t have any form of care policy. So, ultimately, people end up more often than not given the choice of, ‘Do I care for my elderly parents or do I work? Because I can’t do both’.”

He called on ministers to introduce five days of statutory carers leave as promised in the Tory manifesto. The pledge was missing from the Queen’s speech, unveiled in May.

In fact, the extension of life expectancies means that caring for a grandchild or parents – or both – is now a real issue for those in their late 50s, 60s and 70s. Just this weekend, Age UK is warning that the 1.8 million older people caring for loved ones are now dangerously tired and short of support in the wake of the pandemic. More older carers said they were finding it harder to manage everyday activities, such as getting out of bed or dressing. Greater access to breaks, through respite care, is an obvious answer to helping these older carers cope. Yet some of these services have closed since Covid arrived.

For the growing numbers well into their retirement, Joan Bakewell, 89, the Labour peer, author and presenter, says voluntary groups and friendships are hugely important as council services have been stripped back over the austerity years since 2010. “I belong to a book group and a film club. That’s tremendously important and helpful,” said Bakewell, who was due to attend the 90th birthday party of actress Prunella Scales this weekend.

“And it doesn’t need good movies or bad movies or good books or bad books. It’s a social function. My book group has been meeting for 20 years. Those groups tend to look after each other too. They’re not going to be government funded, that’s for sure.”

Bakewell also said it was important to differentiate between the haves and have-nots in old age, a clear theme among those who have thought seriously about Britain’s preparedness for its ageing inhabitants.

Aideen Young says two million people who are 65 are living in poverty. “A huge number have been pushed into poverty as a result of the increase in state pension age,” she said. “Poverty is a big problem.” Another big issue remains popular perception. “The imagery that we have is so pervasive around older people,” she said. “We have to try and tackle this notion that this is somehow an undesirable group that lacks imagination, that lacks ability.”

Anyone who witnessed the exercise class in Cromer would have been cured of any assumptions about the limitations of later life – or the idea that there is a set age to commence winding down. Ann Cunningham, 69, another from the class, says her son has noticed. “He says, ‘When are you free, mum? You’ve retired and I thought you were going to relax and things – but you’re always busy!’”

Global generations

Around the world: Japan has, for some time, been grappling with the issue of its ageing population, with 28.2% of people over 65 in 2019 – the highest proportion in the world, according to United Nations figures compiled by the US Population Reference Bureau. Italy at 22.8% was next highest, followed by Finland, Portugal and Greece. France, whose population is now almost the same as the UK’s, had 20.3% over 65, while Germany, which has 83 million people, has a proportion of 21.4%.

The UK has a younger age profile than most western European countries, but the census has pushed England and Wales up from 16.4% in 2011 to 18.6%.

Youngest places: Nationally, there were just 3.2 million children under the age of four in England and Wales, a significant fall of 7.6% from 3.5 million in 2011.

The youngest people in England and Wales are in suburbs and commuter belt towns clustered around the major cities. Barking and Dagenham, on the London/Essex border, has the largest proportion of young people, with 24.5% of the population under 15 years old. Slough in Berkshire (23.5%) and Luton in Bedfordshire (21.9%) are next.

Birmingham is also a city for the young, according to the census, with 28.5% of its population made up of those aged 0-19. This compares with 23.1% across England and Wales combined.

Oldest places: The proportion of people of pensionable age in the UK has overtaken the proportion of toddlers and schoolchildren, with 18.4% over 65, compared with 17.4% under 15.

Over-65s are more likely to be found in coastal and remote rural areas. The census showed that north Norfolk is the first place in the country where one in three (33.4%) are now at pensionable age. The area stretches from tourist favourite Wells-next-the-Sea at the northern tip, down to the Horsey Gap at the southern end of the district.

The next most densely populated area by over-65s is Rother at 32.4%. This stretches from Camber Sands in East Sussex to Bexhill-on-Sea further west.

Shift of the generations: Comparisons with previous censuses show that most of the rise in population is in people aged over 40 – partly the impact of the postwar baby boom and immigration. There are 3.8 million more over-65s now than there were in 1981, and 5.4 million more 40-64-year-olds.

But there have been declines in some age groups as well. Since 2021, the number of 15-24s is down by 350,000 and 40-49s are down by 650,000.

Tracking cohorts through the years show some significant generational differences caused by immigration. There are almost exactly 4 million people now who were born between 1962 and 1966 – the tail end of the so-called Baby Boomer generation – and their cohort has remained at almost exactly that level at each census since 1981.

Yet there were only 2.9 million born between 1977 and 1981, and their number has risen to nearly 3.8 million, showing how immigration has made up the shortfall in working age population.

Wealth disparity: The Office for National Statistics will release census bulletins delving into issues relating to work, housing and education later this year, but its estimates show that income inequality has changed little since its peak in 2008. According to the ONS, inequality in disposable income fell slightly in 2021 but was broadly in line with the average over the last decade.

Its analysis of household income shows that the richest 1% of households have assets worth at least £3.6m, while the poorest 10% have less than £15,400. The top 10% of households own 43% of all wealth in Great Britain.

James Tapper