Quarter	Billions of US Dollars
1997-07-01	17884.999
1997-10-01	17528.890
1998-01-01	17466.454
1998-04-01	17612.981
1998-07-01	18312.503
1998-10-01	19578.064
1999-01-01	18734.390
1999-04-01	18721.512
1999-07-01	19857.528
1999-10-01	20192.910
2000-01-01	20053.182
2000-04-01	20136.655
2000-07-01	19822.343
2000-10-01	20139.751
2001-01-01	19377.064
2001-04-01	19358.397
2001-07-01	20093.008
2001-10-01	19697.676
2002-01-01	19657.938
2002-04-01	21229.347
2002-07-01	21275.371
2002-10-01	22283.917
2003-01-01	22748.124
2003-04-01	23680.113
2003-07-01	24575.955
2003-10-01	25961.339
2004-01-01	26223.377
2004-04-01	26246.138
2004-07-01	26800.710
2004-10-01	29018.972
2005-01-01	28656.126
2005-04-01	28364.423
2005-07-01	29043.009
2005-10-01	29247.067
2006-01-01	30321.085
2006-04-01	31923.002
2006-07-01	32602.404
2006-10-01	34015.954
2007-01-01	35008.767
2007-04-01	36268.857
2007-07-01	38519.179
2007-10-01	40272.470
2008-01-01	42936.906
2008-04-01	43535.055
2008-07-01	41680.592
2008-10-01	41083.130
2009-01-01	40251.233
2009-04-01	42679.913
2009-07-01	43914.561
2009-10-01	43807.678
2010-01-01	43876.161
2010-04-01	43098.336
2010-07-01	46025.594
2010-10-01	46586.870
2011-01-01	48121.751
2011-04-01	49424.116
2011-07-01	48475.617
2011-10-01	48874.994
2012-01-01	49951.817
2012-04-01	49454.221
2012-07-01	51012.052
2012-10-01	51346.587
2013-01-01	50876.004
2013-04-01	51032.665
2013-07-01	52485.987
2013-10-01	52987.869
2014-01-01	53407.921
2014-04-01	54526.337
2014-07-01	53070.253
2014-10-01	52172.920
2015-01-01	51022.172
2015-04-01	52499.359
2015-07-01	52069.051
2015-10-01	52438.035
2016-01-01	54584.241
2016-04-01	54900.954
2016-07-01	55708.192
2016-10-01	53956.033
2017-01-01	55715.548
2017-04-01	57551.711
2017-07-01	59355.508
2017-10-01	60894.892
2018-01-01	63249.835