Quarter	Millions of US Dollars
1971-01-01	46
1971-04-01	31
1971-07-01	31
1972-04-01	32
1973-04-01	14
1973-10-01	10
1974-01-01	32
1974-04-01	82
1974-10-01	153
1975-01-01	417
1975-04-01	443
1975-07-01	212
1975-10-01	441
1976-01-01	770
1976-04-01	729
1976-07-01	205
1976-10-01	372
1977-01-01	558
1977-04-01	566
1977-07-01	270
1977-10-01	427
1978-01-01	473
1978-04-01	660
1978-07-01	815
1978-10-01	795
1979-01-01	1259
1979-04-01	1060
1979-07-01	1001
1979-10-01	169
1980-01-01	296
1980-04-01	447
1980-07-01	741
1980-10-01	1023
1981-01-01	345
1981-04-01	644
1981-07-01	1575
1981-10-01	771
1982-01-01	1140
1982-04-01	728
1982-07-01	846
1982-10-01	1458
1983-01-01	2129
1983-04-01	2067
1983-07-01	1320
1983-10-01	1882
1984-01-01	3267
1984-04-01	2113
1984-07-01	2867
1984-10-01	1759
1985-01-01	4242
1985-04-01	2687
1985-07-01	4010
1985-10-01	3364
1986-01-01	3816
1986-04-01	6233
1986-07-01	6358
1986-10-01	6608
1987-01-01	5493
1987-04-01	9625
1987-07-01	13609
1987-10-01	3557
1988-01-01	5426
1988-04-01	7507
1988-07-01	15716
1988-10-01	6113
1989-01-01	17689
1989-04-01	28270
1989-07-01	14571
1989-10-01	18200
1990-01-01	7686
1990-04-01	394
1990-07-01	10934
1990-10-01	10224
1991-01-01	6905
1991-04-01	10349
1991-07-01	12227
1991-10-01	9662
1992-01-01	1914
1992-04-01	-351
1992-07-01	-9547
1992-10-01	3739
1993-01-01	-13597
1993-04-01	-17126
1993-07-01	-10695
1993-10-01	-3344
1994-01-01	-1774
1994-04-01	-7242
1994-07-01	-9632
1994-10-01	-9052
1995-01-01	-6234
1995-04-01	-6963
1995-07-01	-14574
1995-10-01	-3385
1996-01-01	-3166
1996-04-01	-2716
1996-07-01	-4003
1996-10-01	-7012
1997-01-01	-6440
1997-04-01	-6230
1997-07-01	-7870
1997-10-01	-10497
1998-01-01	-10676
1998-04-01	-9327
1998-07-01	-5664
1998-10-01	-3125
1999-01-01	-1831
1999-04-01	-380
1999-07-01	-1016
1999-10-01	-6788
2000-01-01	-7948
2000-04-01	-770
2000-07-01	-1489
2000-10-01	-3215
2001-01-01	-2867
2001-04-01	208
2001-07-01	-2777
2001-10-01	1080
2002-01-01	1490
2002-04-01	4042
2002-07-01	-1739
2002-10-01	-2245
2003-01-01	-921
2003-04-01	1443
2003-07-01	-2565
2003-10-01	7745
2004-01-01	3891
2004-04-01	8517
2004-07-01	1069
2004-10-01	2159
2005-01-01	3869
2005-04-01	2695
2005-07-01	5943
2005-10-01	518
2006-01-01	3334
2006-04-01	1800
2006-07-01	1592
2006-10-01	1359
2007-01-01	-1490
2007-04-01	2819
2007-07-01	937
2007-10-01	4662
2008-01-01	-716
2008-04-01	3855
2008-07-01	-908
2008-10-01	-5859
2009-01-01	-5555
2009-04-01	-5599
2009-07-01	-1195
2009-10-01	-681
2010-01-01	3917
2010-04-01	-6954
2010-07-01	6014
2010-10-01	-1624
2011-01-01	1853
2011-04-01	-8446
2011-07-01	-1113
2011-10-01	-3154
2012-01-01	6778
2012-04-01	-4554
2012-07-01	9548
2012-10-01	2515
2013-01-01	8877
2013-04-01	5082
2013-07-01	18471
2013-10-01	4002
2014-01-01	7158
2014-04-01	13614
2014-07-01	14346
2014-10-01	7882
2015-01-01	7598
2015-04-01	-195
2015-07-01	6260
2015-10-01	7549
2016-01-01	8581
2016-04-01	16371
2016-07-01	12494
2016-10-01	8795
2017-01-01	12273
2017-04-01	17753
2017-07-01	41971
2017-10-01	17779
2018-01-01	3292
2018-04-01	5754