The Lancet magazine last month showed the global population is now set to peak at 9.7 billion around 2064 before falling by more than 9% by the end of the century.
While that may be a relief for the environment, it has serious impacts upon economic growth and public debt implications.
Deutsche Bank meanwhile notes that the “central scenario” of Britain’s official fiscal watchdog shows a 2070 government debt/GDP ratio of 418%. During the austerity drive just five years ago, that same 2070 forecast was just 87%.
“It’s almost inconceivable that we’ll reach that point, so something will likely have to give,” said Deutsche strategist Jim Reid, opining on options from cutbacks to age-related pension and healthcare costs, to higher taxes, faster inflation, central bank bond buying or even - whisper it - default. “Economic growth could bail us out but this will be tough given demographics.”
Populations in some 23 of the 195 countries in the study - including Japan, Spain, Portugal, Thailand and Ukraine - are expected to halve by the end of the century and China could see a drop of 48%. Another 33 countries are seen declining by between 25% and 50%. Both China and India should expect to see their numbers peak before 2050.
Add in ageing in countries forecast to see 25% population declines and the ratio of those over 80 to those under 15 is expected to balloon to 1.5 from just 0.16 now.
Helped by immigration, the population of the United States is expected to grow until mid-century followed by a moderate decline of less than 10% of the peak by 2100.