However, its impact on the global economy remained relatively limited until the summer of 2008. However, after the collapse of Lehman Brothers last September, the tensions in global financial markets escalated to a full-blown financial crisis and thereafter turned into a global economic crisis. The severe global economic downturn has now become more synchronised.
  Second, policies in the different countries relied on different components of the balance sheet and affected different markets, mainly because economic and financial structures differed and so did optimal policies.   Third, differences appear not only between countries but also over time. During the most critical initial phase, around the failure of Lehman, all central banks focused on bank refinancing markets.