Quarter	Millions of US Dollars
1966-07-01	15
1967-01-01	14
1972-04-01	32
1972-07-01	21
1972-10-01	45
1973-01-01	37
1973-04-01	51
1973-07-01	36
1973-10-01	60
1974-01-01	52
1974-04-01	49
1974-07-01	167
1974-10-01	296
1975-01-01	398
1975-04-01	493
1975-07-01	139
1975-10-01	19
1976-01-01	100
1976-04-01	64
1976-07-01	145
1976-10-01	327
1977-01-01	342
1977-04-01	285
1977-07-01	381
1977-10-01	235
1978-01-01	267
1978-04-01	360
1978-07-01	342
1978-10-01	312
1979-01-01	306
1979-04-01	185
1979-07-01	289
1979-10-01	77
1980-01-01	230
1980-04-01	369
1980-07-01	489
1980-10-01	336
1981-01-01	297
1981-04-01	392
1981-07-01	200
1981-10-01	413
1982-01-01	465
1982-04-01	260
1982-07-01	127
1982-10-01	89
1983-01-01	188
1983-04-01	262
1983-07-01	195
1983-10-01	-81
1984-01-01	305
1984-04-01	324
1984-07-01	154
1984-10-01	188
1985-01-01	218
1985-04-01	409
1985-07-01	329
1985-10-01	-110
1986-01-01	694
1986-04-01	885
1986-07-01	490
1986-10-01	143
1987-01-01	861
1987-04-01	510
1987-07-01	1
1987-10-01	823
1988-01-01	2042
1988-04-01	569
1988-07-01	511
1988-10-01	161
1989-01-01	781
1989-04-01	587
1989-07-01	101
1989-10-01	815
1990-01-01	1008
1990-04-01	888
1990-07-01	595
1990-10-01	579
1991-01-01	1520
1991-04-01	-73
1991-07-01	652
1991-10-01	1045
1992-01-01	1182
1992-04-01	1212
1992-07-01	724
1992-10-01	140
1993-01-01	878
1993-04-01	1171
1993-07-01	1609
1993-10-01	1457
1994-01-01	1974
1994-04-01	70
1994-07-01	279
1994-10-01	2266
1995-01-01	4041
1995-04-01	565
1995-07-01	249
1995-10-01	1075
1996-01-01	2984
1996-04-01	1436
1996-07-01	294
1996-10-01	100
1997-01-01	1914
1997-04-01	827
1997-07-01	1514
1997-10-01	-1003
1998-01-01	2559
1998-04-01	1703
1998-07-01	1086
1998-10-01	3071
1999-01-01	5662
1999-04-01	3860
1999-07-01	-1091
1999-10-01	1355
2000-01-01	6169
2000-04-01	2594
2000-07-01	3446
2000-10-01	-1786
2001-01-01	7800
2001-04-01	1111
2001-07-01	476
2001-10-01	3777
2002-01-01	10472
2002-04-01	4155
2002-07-01	95
2002-10-01	-89
2003-01-01	7601
2003-04-01	10960
2003-07-01	3859
2003-10-01	2488
2004-01-01	13420
2004-04-01	5416
2004-07-01	3567
2004-10-01	-941
2005-01-01	19074
2005-04-01	13526
2005-07-01	-787
2005-10-01	3762
2006-01-01	12325
2006-04-01	13136
2006-07-01	2710
2006-10-01	10306
2007-01-01	34755
2007-04-01	13985
2007-07-01	8415
2007-10-01	-12613
2008-01-01	15556
2008-04-01	-3432
2008-07-01	644
2008-10-01	10270
2009-01-01	8411
2009-04-01	1575
2009-07-01	761
2009-10-01	-7542
2010-01-01	2919
2010-04-01	-3570
2010-07-01	123
2010-10-01	-5977
2011-01-01	10433
2011-04-01	-9896
2011-07-01	3066
2011-10-01	-8677
2012-01-01	-10161
2012-04-01	-2793
2012-07-01	205
2012-10-01	-1742
2013-01-01	-4058
2013-04-01	1553
2013-07-01	4315
2013-10-01	-4210
2014-01-01	-15844
2014-04-01	987
2014-07-01	-8020
2014-10-01	5184
2015-01-01	-1721
2015-04-01	-227
2015-07-01	-2601
2015-10-01	-5364
2016-01-01	4192
2016-04-01	-4822
2016-07-01	-7152
2016-10-01	2247
2017-01-01	3485
2017-04-01	3132
2017-07-01	-392
2017-10-01	-4722
2018-01-01	4038
2018-04-01	322