As fewer children are born, and the overall population age temporarily rises, this leads to problems making pension and health care cost commitments. That in turn is leading to greater government deficits as they spend the money they don’t have – which in turn is leading to reducing the credit ratings of many governments, world wide. That in turn leads to increase borrowing costs.

Ageing populations ‘already hitting’ governments’ credit ratings | Financial Times (ft.com)

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