Quarter	Billions of US Dollars
1971-01-01	0.06
1971-04-01	0.09
1971-07-01	0.11
1971-10-01	0.20
1972-01-01	0.45
1972-04-01	0.61
1972-07-01	0.82
1972-10-01	1.24
1973-01-01	1.45
1973-04-01	1.95
1973-07-01	2.08
1973-10-01	2.54
1974-01-01	2.72
1974-04-01	3.20
1974-07-01	3.24
1974-10-01	3.49
1975-01-01	3.87
1975-04-01	4.42
1975-07-01	4.48
1975-10-01	4.67
1976-01-01	4.91
1976-04-01	5.38
1976-07-01	6.07
1976-10-01	6.71
1977-01-01	7.39
1977-04-01	8.31
1977-07-01	9.66
1977-10-01	11.34
1978-01-01	13.35
1978-04-01	14.76
1978-07-01	16.31
1978-10-01	17.61
1979-01-01	18.28
1979-04-01	18.96
1979-07-01	20.31
1979-10-01	20.42
1980-01-01	19.30
1980-04-01	21.10
1980-07-01	21.53
1980-10-01	21.28
1981-01-01	20.77
1981-04-01	20.46
1981-07-01	21.12
1981-10-01	22.59
1982-01-01	22.78
1982-04-01	22.68
1982-07-01	22.26
1982-10-01	23.58
1983-01-01	23.00
1983-04-01	22.84
1983-07-01	23.95
1983-10-01	23.72
1984-01-01	24.38
1984-04-01	23.77
1984-07-01	23.39
1984-10-01	24.40
1985-01-01	25.30
1985-04-01	27.54
1985-07-01	29.83
1985-10-01	30.60
1986-01-01	32.85
1986-04-01	34.35
1986-07-01	35.74
1986-10-01	35.12
1987-01-01	36.63
1987-04-01	36.13
1987-07-01	36.01
1987-10-01	39.28
1988-01-01	38.99
1988-04-01	36.77
1988-07-01	36.74
1988-10-01	39.02
1989-01-01	38.12
1989-04-01	36.55
1989-07-01	39.27
1989-10-01	40.54
1990-01-01	75.65
1990-04-01	76.84
1990-07-01	80.40
1990-10-01	98.15
1991-01-01	97.48
1991-04-01	100.92
1991-07-01	104.42
1991-10-01	112.20
1992-01-01	115.17
1992-04-01	120.99
1992-07-01	127.54
1992-10-01	130.45
1993-01-01	135.73
1993-04-01	159.68
1993-07-01	167.29
1993-10-01	188.50
1994-01-01	203.10
1994-04-01	252.99
1994-07-01	266.68
1994-10-01	278.50
1995-01-01	289.82
1995-04-01	297.04
1995-07-01	302.99
1995-10-01	309.29
1996-01-01	318.90
1996-04-01	331.71
1996-07-01	350.34
1996-10-01	370.80
1997-01-01	389.91
1997-04-01	422.26
1997-07-01	442.05
1997-10-01	442.10
1998-01-01	450.63
1998-04-01	472.10
1998-07-01	485.28
1998-10-01	466.89
1999-01-01	463.36
1999-04-01	476.56
1999-07-01	483.47
1999-10-01	490.86
2000-01-01	505.76
2000-04-01	509.00
2000-07-01	536.76
2000-10-01	534.64
2001-01-01	537.40
2001-04-01	532.48
2001-07-01	539.37
2001-10-01	531.69
2002-01-01	535.35
2002-04-01	553.04
2002-07-01	553.21
2002-10-01	562.83
2003-01-01	566.75
2003-04-01	576.59
2003-07-01	588.58
2003-10-01	607.15
2004-01-01	621.86
2004-04-01	630.03
2004-07-01	638.65
2004-10-01	668.15
2005-01-01	681.91
2005-04-01	662.13
2005-07-01	668.62
2005-10-01	684.71
2006-01-01	719.24
2006-04-01	717.90
2006-07-01	735.68
2006-10-01	778.02
2007-01-01	804.22
2007-04-01	846.64
2007-07-01	864.16
2007-10-01	889.88
2008-01-01	904.25
2008-04-01	925.78
2008-07-01	905.08
2008-10-01	880.53
2009-01-01	873.57
2009-04-01	908.37
2009-07-01	953.89
2009-10-01	991.28
2010-01-01	1003.05
2010-04-01	1017.09
2010-07-01	1079.05
2010-10-01	1115.58
2011-01-01	1175.11
2011-04-01	1220.27
2011-07-01	1218.27
2011-10-01	1246.34
2012-01-01	1296.44
2012-04-01	1325.66
2012-07-01	1397.55
2012-10-01	1470.03
2013-01-01	1495.24
2013-04-01	1543.82
2013-07-01	1602.49
2013-10-01	1675.05
2014-01-01	1698.79
2014-04-01	1755.44
2014-07-01	1770.36
2014-10-01	1815.78
2015-01-01	1818.30
2015-04-01	1876.09