Quarter	Millions of US Dollars
1973-01-01	0
1973-04-01	0
1973-07-01	0
1973-10-01	0
1974-01-01	0
1974-04-01	0
1974-07-01	0
1974-10-01	0
1975-01-01	0
1975-04-01	0
1975-07-01	0
1975-10-01	0
1976-01-01	0
1976-04-01	0
1976-07-01	0
1976-10-01	0
1977-01-01	0
1977-04-01	0
1977-07-01	0
1977-10-01	0
1978-01-01	0
1978-04-01	0
1978-07-01	0
1978-10-01	0
1979-01-01	0
1979-04-01	0
1979-07-01	0
1979-10-01	0
1980-01-01	0
1980-04-01	0
1980-07-01	0
1980-10-01	0
1981-01-01	0
1981-04-01	0
1981-07-01	0
1981-10-01	0
1982-01-01	0
1982-04-01	0
1982-07-01	0
1982-10-01	0
1983-01-01	0
1983-04-01	0
1983-07-01	0
1983-10-01	0
1984-01-01	25
1984-04-01	55
1984-07-01	55
1984-10-01	70
1985-01-01	46
1985-04-01	16
1985-07-01	16
1985-10-01	2
1986-01-01	2
1986-04-01	3
1986-07-01	4
1986-10-01	2
1987-01-01	2
1987-04-01	2
1987-07-01	26
1987-10-01	26
1988-01-01	25
1988-04-01	25
1988-07-01	0
1988-10-01	0
1989-01-01	0
1989-04-01	0
1989-07-01	0
1989-10-01	0
1990-01-01	0
1990-04-01	0
1990-07-01	0
1990-10-01	0
1991-01-01	0
1991-04-01	50
1991-07-01	50
1991-10-01	50
1992-01-01	50
1992-04-01	0
1992-07-01	0
1992-10-01	0
1993-01-01	0
1993-04-01	0
1993-07-01	57
1993-10-01	54
1994-01-01	58
1994-04-01	61
1994-07-01	45
1994-10-01	30
1995-01-01	230
1995-04-01	295
1995-07-01	295
1995-10-01	360
1996-01-01	160
1996-04-01	120
1996-07-01	95
1996-10-01	50
1997-01-01	50
1997-04-01	175
1997-07-01	325
1997-10-01	275
1998-01-01	350
1998-04-01	222
1998-07-01	199
1998-10-01	256
1999-01-01	169
1999-04-01	301
1999-07-01	176
1999-10-01	356
2000-01-01	351
2000-04-01	616
2000-07-01	841
2000-10-01	760
2001-01-01	962
2001-04-01	1270
2001-07-01	1172
2001-10-01	1028
2002-01-01	1185
2002-04-01	1255
2002-07-01	1258
2002-10-01	1292
2003-01-01	1771
2003-04-01	978
2003-07-01	863
2003-10-01	863
2004-01-01	0
2004-04-01	184
2004-07-01	1166
2004-10-01	2010
2005-01-01	2446
2005-04-01	2982
2005-07-01	2166
2005-10-01	1544
2006-01-01	1559
2006-04-01	1056
2006-07-01	871
2006-10-01	921
2007-01-01	1684
2007-04-01	1670
2007-07-01	1727
2007-10-01	1617
2008-01-01	239
2008-04-01	885
2008-07-01	885
2008-10-01	885
2009-01-01	1372
2009-04-01	794
2009-07-01	1146
2009-10-01	1707
2010-01-01	1096
2010-04-01	1669
2010-07-01	1443
2010-10-01	1570
2011-01-01	2727
2011-04-01	1862
2011-07-01	1862
2011-10-01	1414
2012-01-01	1359
2012-04-01	1368
2012-07-01	1375
2012-10-01	1085
2013-01-01	996
2013-04-01	996
2013-07-01	1526
2013-10-01	2696
2014-01-01	1700
2014-04-01	1700
2014-07-01	1190
2014-10-01	1295
2015-01-01	1844
2015-04-01	2010
2015-07-01	1818
2015-10-01	936
2016-01-01	2594
2016-04-01	3638
2016-07-01	3638
2016-10-01	3522
2017-01-01	2488
2017-04-01	1922
2017-07-01	1986
2017-10-01	1962
2018-01-01	2713
2018-04-01	2012