After the stock market crash of 1987, The Federal Reserve embarked on a path that led to the biggest debt bubble in the history of the world. The day after the 1987 crash (Oct. 20, 1987) Alan Greenspan, Chairman of the Fed, announced to the world that The Fed stood ready to provide whatever liquidity was needed by the banking system to prevent the crash from turning into a systemic financial crisis. That was the day the Fed put was born.... read more
http://www.zerohedge.com/news/2016-03-31/2016-end-global-debt-super-cycle
Why is the y-axis in log? That distorts the chart and makes a meaningful comparison of the two lines meaningless, although perhaps it advances a particular narrative.