Quarter	Millions of US Dollars
1972-10-01	0
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	18
1978-07-01	18
1978-10-01	18
1979-01-01	18
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	12
1981-01-01	12
1981-04-01	12
1981-07-01	12
1981-10-01	0
1982-01-01	17
1982-04-01	17
1982-07-01	17
1982-10-01	17
1983-01-01	21
1983-04-01	21
1983-07-01	59
1983-10-01	58
1984-01-01	77
1984-04-01	72
1984-07-01	33
1984-10-01	83
1985-01-01	63
1985-04-01	64
1985-07-01	170
1985-10-01	182
1986-01-01	175
1986-04-01	244
1986-07-01	165
1986-10-01	75
1987-01-01	176
1987-04-01	107
1987-07-01	127
1987-10-01	194
1988-01-01	141
1988-04-01	138
1988-07-01	175
1988-10-01	126
1989-01-01	70
1989-04-01	96
1989-07-01	112
1989-10-01	109
1990-01-01	102
1990-04-01	79
1990-07-01	0
1990-10-01	111
1991-01-01	314
1991-04-01	316
1991-07-01	320
1991-10-01	207
1992-01-01	0
1992-04-01	0
1992-07-01	0
1992-10-01	0
1993-01-01	0
1993-04-01	0
1993-07-01	30
1993-10-01	45
1994-01-01	30
1994-04-01	138
1994-07-01	109
1994-10-01	111
1995-01-01	276
1995-04-01	207
1995-07-01	343
1995-10-01	489
1996-01-01	398
1996-04-01	397
1996-07-01	262
1996-10-01	405
1997-01-01	403
1997-04-01	558
1997-07-01	1290
1997-10-01	1093
1998-01-01	1933
1998-04-01	1907
1998-07-01	1487
1998-10-01	2297
1999-01-01	1659
1999-04-01	2155
1999-07-01	2288
1999-10-01	1292
2000-01-01	1894
2000-04-01	1500
2000-07-01	1475
2000-10-01	1639
2001-01-01	1147
2001-04-01	2303
2001-07-01	2475
2001-10-01	2620
2002-01-01	2448
2002-04-01	1977
2002-07-01	1695
2002-10-01	1425
2003-01-01	2660
2003-04-01	2972
2003-07-01	3150
2003-10-01	3064
2004-01-01	1705
2004-04-01	1325
2004-07-01	947
2004-10-01	1915
2005-01-01	1671
2005-04-01	2247
2005-07-01	2043
2005-10-01	2395
2006-01-01	2614
2006-04-01	2119
2006-07-01	2280
2006-10-01	1186
2007-01-01	1171
2007-04-01	2482
2007-07-01	2283
2007-10-01	2157
2008-01-01	2552
2008-04-01	1696
2008-07-01	1575
2008-10-01	1278
2009-01-01	2336
2009-04-01	2444
2009-07-01	2762
2009-10-01	3307
2010-01-01	2832
2010-04-01	2606
2010-07-01	2609
2010-10-01	3018
2011-01-01	1870
2011-04-01	1889
2011-07-01	1616
2011-10-01	720
2012-01-01	2329
2012-04-01	2328
2012-07-01	2829
2012-10-01	2721
2013-01-01	2299
2013-04-01	2899
2013-07-01	2856
2013-10-01	2856
2014-01-01	2456
2014-04-01	1856
2014-07-01	1705
2014-10-01	1805
2015-01-01	2042
2015-04-01	2712
2015-07-01	2309
2015-10-01	3282
2016-01-01	4571
2016-04-01	3921
2016-07-01	3921
2016-10-01	4411
2017-01-01	1573
2017-04-01	1923
2017-07-01	2768
2017-10-01	1400
2018-01-01	2500
2018-04-01	4948