Quarter	Billions of US Dollars
1971-01-01	0.03
1971-04-01	0.03
1971-07-01	0.03
1971-10-01	0.03
1972-01-01	0.03
1972-04-01	0.03
1972-07-01	0.03
1972-10-01	0.06
1973-01-01	0.11
1973-04-01	0.14
1973-07-01	0.21
1973-10-01	0.20
1974-01-01	0.23
1974-04-01	0.27
1974-07-01	0.26
1974-10-01	0.32
1975-01-01	0.33
1975-04-01	0.33
1975-07-01	0.30
1975-10-01	0.34
1976-01-01	0.35
1976-04-01	0.35
1976-07-01	0.38
1976-10-01	0.38
1977-01-01	0.41
1977-04-01	0.41
1977-07-01	0.48
1977-10-01	0.52
1978-01-01	0.55
1978-04-01	0.63
1978-07-01	0.70
1978-10-01	0.69
1979-01-01	0.67
1979-04-01	0.72
1979-07-01	0.84
1979-10-01	0.90
1980-01-01	0.93
1980-04-01	1.02
1980-07-01	1.01
1980-10-01	1.07
1981-01-01	1.11
1981-04-01	1.14
1981-07-01	1.08
1981-10-01	1.46
1982-01-01	1.68
1982-04-01	1.75
1982-07-01	1.88
1982-10-01	2.00
1983-01-01	2.21
1983-04-01	2.28
1983-07-01	2.29
1983-10-01	2.91
1984-01-01	2.99
1984-04-01	2.96
1984-07-01	3.21
1984-10-01	3.41
1985-01-01	3.84
1985-04-01	4.07
1985-07-01	4.58
1985-10-01	5.15
1986-01-01	5.52
1986-04-01	6.23
1986-07-01	7.49
1986-10-01	7.59
1987-01-01	7.73
1987-04-01	7.86
1987-07-01	7.76
1987-10-01	8.19
1988-01-01	8.21
1988-04-01	7.92
1988-07-01	7.49
1988-10-01	7.73
1989-01-01	7.10
1989-04-01	7.14
1989-07-01	8.84
1989-10-01	9.22
1990-01-01	9.69
1990-04-01	10.10
1990-07-01	10.66
1990-10-01	11.08
1991-01-01	10.34
1991-04-01	10.84
1991-07-01	11.59
1991-10-01	12.20
1992-01-01	11.92
1992-04-01	12.25
1992-07-01	13.27
1992-10-01	13.47
1993-01-01	15.98
1993-04-01	15.88
1993-07-01	16.17
1993-10-01	15.61
1994-01-01	15.48
1994-04-01	16.31
1994-07-01	16.47
1994-10-01	16.16
1995-01-01	17.96
1995-04-01	18.92
1995-07-01	18.96
1995-10-01	21.25
1996-01-01	21.10
1996-04-01	21.83
1996-07-01	23.62
1996-10-01	26.65
1997-01-01	29.43
1997-04-01	31.23
1997-07-01	32.13
1997-10-01	34.00
1998-01-01	34.60
1998-04-01	36.78
1998-07-01	39.43
1998-10-01	39.23
1999-01-01	37.68
1999-04-01	37.95
1999-07-01	42.23
1999-10-01	44.25
2000-01-01	44.95
2000-04-01	46.17
2000-07-01	46.16
2000-10-01	47.60
2001-01-01	51.35
2001-04-01	52.93
2001-07-01	56.49
2001-10-01	58.46
2002-01-01	60.64
2002-04-01	70.23
2002-07-01	71.78
2002-10-01	81.55
2003-01-01	92.35
2003-04-01	108.22
2003-07-01	125.01
2003-10-01	166.55
2004-01-01	179.99
2004-04-01	198.57
2004-07-01	226.39
2004-10-01	276.68
2005-01-01	294.55
2005-04-01	322.97
2005-07-01	332.97
2005-10-01	366.31
2006-01-01	411.68
2006-04-01	493.24
2006-07-01	565.04
2006-10-01	660.46
2007-01-01	718.57
2007-04-01	821.37
2007-07-01	912.58
2007-10-01	975.89
2008-01-01	1068.17
2008-04-01	1100.63
2008-07-01	1026.77
2008-10-01	1065.18
2009-01-01	1057.97
2009-04-01	1163.23
2009-07-01	1230.16
2009-10-01	1211.98
2010-01-01	1160.68
2010-04-01	1071.09
2010-07-01	1144.54
2010-10-01	1117.59
2011-01-01	1131.35
2011-04-01	1138.43
2011-07-01	1052.19
2011-10-01	1013.47
2012-01-01	1032.10
2012-04-01	959.80
2012-07-01	965.60
2012-10-01	981.87
2013-01-01	957.84
2013-04-01	957.97
2013-07-01	968.16
2013-10-01	991.76
2014-01-01	992.73
2014-04-01	983.20
2014-07-01	898.43
2014-10-01	825.21
2015-01-01	723.45
2015-04-01	777.46