Quarter Billions of US Dollars 2011-10-01 0.21742 2012-01-01 0.23868 2012-04-01 0.21330 2012-07-01 0.22641 2014-07-01 1.00000 2014-10-01 1.00000 2015-01-01 1.00000 2015-04-01 1.00000