In the years since the 2008 global financial crisis, austerity and balance-sheet repair have been the watchwords of the global economy. And yet today debt is fueling concern about growth prospects worldwide. The McKinsey Global Institute notes in a study that gross debt has increased about $60 trillion – or 75% of global GDP – since 2008. China’s debt, for example, has increased fourfold since 2007, and its debt-to-GDP ratio is some 282% – higher than in many other major economies, including the United States. A global economy that is levering up, while unable to generate enough aggregate demand to achieve potential growth, is on a risky path. But to assess how risky, several factors must be considered.