The macro-financial factors behind the crisis: Global liquidity glut or global savings glut?

It has been argued that the global financial crisis 2007–2009 was intrinsically related to two largely unprecedented phenomena in the global economy: (i) exceptionally benign financial market conditions as mirrored in historically low risk premia and buoyant asset price developments as well as (ii) an unprecedented widening of external imbalances. This paper explores to what extent these global trends can be understood as a reaction to three structural shocks to the macro-financial environment of the global economy: (i) monetary shocks (“excess liquidity” hypothesis), (ii) preference shocks (“savings glut” hypothesis), and (iii) investment shocks (“investment drought” hypothesis). In order to uniquely identify these shocks in an integrated framework, we estimate structural VARs for the two main regions with widening imbalances, the United States and emerging Asia, using sign restrictions that are compatible with standard New Keynesian and Real Business Cycle models. Our results show that (US) monetary policy shocks explain the largest part of the variation in imbalances and financial market prices. We find that savings shocks and investment shocks explain less of the variation. Hence, a “liquidity glut” may have been a more important driver of real and financial imbalances in the US and emerging Asia that ultimately triggered the global financial crisis.