Quarter	Billions of US Dollars
1999-01-01	25.737
1999-04-01	25.307
1999-07-01	25.791
1999-10-01	30.094
2000-01-01	26.682
2000-04-01	26.700
2000-07-01	26.936
2000-10-01	32.120
2001-01-01	37.631
2001-04-01	38.765
2001-07-01	37.960
2001-10-01	35.803
2002-01-01	34.662
2002-04-01	35.448
2002-07-01	39.202
2002-10-01	36.429
2003-01-01	37.166
2003-04-01	37.617
2003-07-01	40.525
2003-10-01	43.391
2004-01-01	46.626
2004-04-01	47.438
2004-07-01	46.893
2004-10-01	46.374
2005-01-01	43.476
2005-04-01	43.488
2005-07-01	46.272
2005-10-01	42.056
2006-01-01	41.731
2006-04-01	41.496
2006-07-01	45.759
2006-10-01	42.066
2007-01-01	41.394
2007-04-01	41.155
2007-07-01	42.024
2007-10-01	44.225
2008-01-01	45.062
2008-04-01	45.303
2008-07-01	56.340
2008-10-01	69.478
2009-01-01	78.084
2009-04-01	99.595
2009-07-01	113.285
2009-10-01	135.818
2010-01-01	134.071
2010-04-01	134.067
2010-07-01	135.589
2010-10-01	139.523
2011-01-01	140.638
2011-04-01	141.716
2011-07-01	143.937
2011-10-01	146.381
2012-01-01	144.807
2012-04-01	147.140
2012-07-01	160.743
2012-10-01	168.352
2013-01-01	174.134
2013-04-01	175.027
2013-07-01	184.236
2013-10-01	182.760
2014-01-01	179.787
2014-04-01	186.402
2014-07-01	209.584
2014-10-01	194.941
2015-01-01	202.978
2015-04-01	210.189
2015-07-01	219.792
2015-10-01	228.239
2016-01-01	229.157
2016-04-01	231.485
2016-07-01	235.270
2016-10-01	233.575
2017-01-01	234.791
2017-04-01	237.260
2017-07-01	237.960
2017-10-01	240.794
2018-01-01	243.368