Quarter	Millions of US Dollars
1971-10-01	15
1973-07-01	77
1974-01-01	50
1975-01-01	24
1977-04-01	107
1977-07-01	21
1978-07-01	-48
1981-10-01	55
1982-07-01	23
1982-10-01	40
1983-10-01	50
1984-07-01	-13
1984-10-01	75
1985-01-01	36
1985-04-01	-64
1985-07-01	-50
1985-10-01	24
1986-04-01	-36
1986-07-01	94
1986-10-01	26
1987-04-01	214
1988-01-01	156
1988-04-01	6
1988-07-01	-24
1989-04-01	128
1989-10-01	-50
1990-04-01	117
1991-01-01	-67
1991-04-01	274
1991-07-01	155
1991-10-01	-85
1992-04-01	24
1992-07-01	-7
1992-10-01	2
1993-01-01	2
1993-04-01	159
1993-07-01	1680
1993-10-01	2669
1994-01-01	2137
1994-04-01	764
1994-07-01	1078
1994-10-01	1960
1995-01-01	-26
1995-04-01	-245
1995-07-01	72
1995-10-01	818
1996-01-01	1788
1996-04-01	-953
1996-07-01	1125
1996-10-01	600
1997-01-01	1880
1997-04-01	2484
1997-07-01	3219
1997-10-01	-346
1998-01-01	163
1998-04-01	-222
1998-07-01	-418
1998-10-01	-868
1999-01-01	2814
1999-04-01	-72
1999-07-01	725
1999-10-01	-469
2000-01-01	899
2000-04-01	-108
2000-07-01	4446
2000-10-01	142
2001-01-01	3472
2001-04-01	3729
2001-07-01	-46
2001-10-01	1166
2002-01-01	1403
2002-04-01	803
2002-07-01	-104
2002-10-01	-158
2003-01-01	2006
2003-04-01	951
2003-07-01	-119
2003-10-01	4672
2004-01-01	-547
2004-04-01	-616
2004-07-01	1279
2004-10-01	1454
2005-01-01	1562
2005-04-01	1954
2005-07-01	2135
2005-10-01	638
2006-01-01	52
2006-04-01	1142
2006-07-01	1025
2006-10-01	3221
2007-01-01	273
2007-04-01	3493
2007-07-01	-1246
2007-10-01	473
2008-01-01	-273
2008-04-01	2192
2008-07-01	1508
2008-10-01	-1484
2009-01-01	-1406
2009-04-01	2540
2009-07-01	5863
2009-10-01	3351
2010-01-01	898
2010-04-01	-24
2010-07-01	4145
2010-10-01	2906
2011-01-01	-3024
2011-04-01	3095
2011-07-01	130
2011-10-01	346
2012-01-01	12943
2012-04-01	8300
2012-07-01	2529
2012-10-01	3733
2013-01-01	1688
2013-04-01	5423
2013-07-01	-2153
2013-10-01	1587
2014-01-01	6047
2014-04-01	1850
2014-07-01	1760
2014-10-01	4855
2015-01-01	3365
2015-04-01	-1206
2015-07-01	-3530
2015-10-01	1140
2016-01-01	851
2016-04-01	5516
2016-07-01	1505
2016-10-01	4918
2017-01-01	-1052
2017-04-01	5875
2017-07-01	8960
2017-10-01	1763
2018-01-01	2394
2018-04-01	2981