The researchers from McGill University in Montreal noted a convergence in the rateof deaths from HIV and heart disease as contributing to the narrowing of the life expectancy gap.
Dr Melnick explained that to predict an earthquake's magnitude, seismologists multiply plate convergencerate by the number of years since the last great event.
The pattern of swift, uninterrupted decline is now taken as the norm: the UN uses it to project a worldwide convergence towards the replacement rateof fertility (2.1, the rate at which a population stabilises in the long term).
The convergence in yields reflects mainly the removal of exchange-rate risk since the creation of the single currency, but that still leaves default risk.