The front-runner to become Britain's seventh prime minister in ten years is Andy Burnham. The reasons so many have come and gone in that time are largely economic. The people's tolerance with successive administrations has been damaged by stagnant living standards, overburdened public services, and a continuous lack of investment. Burnham will inherit all of it.

His first constraint is fiscal. He has promised to follow the present government's borrowing guidelines, which include using debt primarily to finance investments rather than ongoing expenses and reducing the total debt load as a percentage of GDP over a predetermined period of time. Before the US-Israel-Iran conflict, the Treasury estimated a headroom of £24bn against those rules. Much of that cushion has probably gone. Debt interest already accounts for one in every ten pounds the government spends, which limits the space for manoeuvre and makes bond markets a constant consideration. Burnham has indicated he understands this. Whether his ambitions survive it is another matter.

On living standards, the picture is one of prolonged deterioration. Household earnings increased by around 2.5% annually between 1990 and 2007. The rate has decreased by around half since then. Low investment during the austerity years, the disruption of Brexit, the economic shock of the pandemic and a sustained rise in energy prices have all weighed on productivity and, by extension, wages. Food prices have increased by 40 per cent in a short period. Burnham has spoken about increasing investment and bringing utilities under greater state control, but the details of how either would work in practice remain vague.

Employment is a related concern. Hiring has been at its lowest point in five years. Young people have been hit hardest, partly because the sectors that typically provide entry-level work have contracted. Higher national minimum wages and increased employer tax contributions have accelerated job losses in retail and hospitality, precisely the industries that absorb workers with few qualifications. A recent report by former Labour minister Alan Milburn found that the erosion of such roles has contributed to rising youth joblessness. He cautioned that one in six young people might not be employed, enrolled in school, or receiving training. Later this year, a second edition of that study with policy suggestions is anticipated.

Defence adds further pressure. By 2035, the government plans to increase defence expenditures to 3.5% of GDP. Burnham has signalled support for that target. Tens of billions of pounds will be needed to get there. The former defence secretary, John Healey, resigned because he believed the Treasury was unwilling to provide the required funding. Funding the increase without cutting elsewhere will be extremely difficult, given that many departments are already facing tight settlements.

Welfare spending is also rising fast. It is projected to increase by more than a quarter between 2025 and 2030, driven primarily by sickness-related payments to working-age adults and pensioner benefits. Reform of the triple lock, which raises the state pension each year by the highest of earnings growth, inflation or 2.5 per cent, is one option. Lord Jim O'Neill, one of Burnham's own advisers, is among the economists who have argued for simplifying the formula. Doing so could save tens of billions over time. It would also mean lower pension increases for the most reliably voting segment of the electorate.

Housing rounds out an already crowded picture. Mortgage affordability has improved slightly from recent peaks, but high rents make accumulating a deposit difficult for many prospective buyers, and the average age of first-time buyers has risen. Housebuilding fell 6 per cent last year, leaving the government well short of its 300,000 annual target. Burnham has expressed support for more social housing. The obstacles that have frustrated every administration before him have not gone away.

The premise of Burnham's prospectus is that increased expenditure today leads to growth in the future. It is a coherent position, but it depends on fiscal room that may not exist, and on growth that has proved elusive for nearly two decades. The question of where the money comes from has not yet been answered.