Quarter	Millions of US Dollars
1960-01-01	-49
1960-04-01	24
1960-07-01	29
1960-10-01	15
1961-01-01	-46
1961-04-01	-35
1961-07-01	134
1961-10-01	40
1962-01-01	10
1962-04-01	138
1962-07-01	136
1962-10-01	47
1963-01-01	35
1963-04-01	84
1963-07-01	61
1963-10-01	50
1964-01-01	46
1964-04-01	112
1964-07-01	46
1964-10-01	21
1965-01-01	193
1965-04-01	-3
1965-07-01	-16
1965-10-01	208
1966-01-01	97
1966-04-01	299
1966-07-01	241
1966-10-01	56
1967-01-01	-33
1967-04-01	145
1967-07-01	192
1967-10-01	43
1968-01-01	142
1968-04-01	311
1968-07-01	225
1968-10-01	23
1969-01-01	154
1969-04-01	263
1969-07-01	13
1969-10-01	-24
1970-01-01	7
1970-04-01	82
1970-07-01	152
1970-10-01	-49
1971-01-01	-155
1971-04-01	368
1971-07-01	142
1971-10-01	92
1972-01-01	85
1972-04-01	733
1972-07-01	189
1972-10-01	29
1973-01-01	218
1973-04-01	750
1973-07-01	94
1973-10-01	-139
1974-01-01	148
1974-04-01	-53
1974-07-01	88
1974-10-01	304
1975-01-01	453
1975-04-01	559
1975-07-01	240
1975-10-01	622
1976-01-01	356
1976-04-01	304
1976-07-01	78
1976-10-01	531
1977-01-01	65
1977-04-01	566
1977-07-01	835
1977-10-01	447
1978-01-01	343
1978-04-01	1234
1978-07-01	276
1978-10-01	279
1979-01-01	-74
1979-04-01	503
1979-07-01	102
1979-10-01	903
1980-01-01	-473
1980-04-01	1108
1980-07-01	663
1980-10-01	925
1981-01-01	-713
1981-04-01	1465
1981-07-01	444
1981-10-01	423
1982-01-01	363
1982-04-01	1515
1982-07-01	685
1982-10-01	969
1983-01-01	12
1983-04-01	1619
1983-07-01	579
1983-10-01	63
1984-01-01	345
1984-04-01	1983
1984-07-01	-112
1984-10-01	799
1985-01-01	349
1985-04-01	1704
1985-07-01	-135
1985-10-01	444
1986-01-01	352
1986-04-01	1216
1986-07-01	804
1986-10-01	374
1987-01-01	391
1987-04-01	1450
1987-07-01	736
1987-10-01	1085
1988-01-01	393
1988-04-01	2122
1988-07-01	1584
1988-10-01	982
1989-01-01	983
1989-04-01	2346
1989-07-01	1504
1989-10-01	1050
1990-01-01	-541
1990-04-01	1412
1990-07-01	1468
1990-10-01	1099
1991-01-01	853
1991-04-01	3261
1991-07-01	895
1991-10-01	2151
1992-01-01	431
1992-04-01	5593
1992-07-01	2991
1992-10-01	738
1993-01-01	2481
1993-04-01	5471
1993-07-01	2940
1993-10-01	296
1994-01-01	3991
1994-04-01	3883
1994-07-01	2047
1994-10-01	2698
1995-01-01	975
1995-04-01	3641
1995-07-01	4267
1995-10-01	800
1996-01-01	2683
1996-04-01	1884
1996-07-01	2595
1996-10-01	650
1997-01-01	1813
1997-04-01	2684
1997-07-01	924
1997-10-01	1418
1998-01-01	1039
1998-04-01	1479
1998-07-01	1596
1998-10-01	258
1999-01-01	1085
1999-04-01	1221
1999-07-01	703
1999-10-01	-763
2000-01-01	466
2000-04-01	1149
2000-07-01	693
2000-10-01	-387
2001-01-01	174
2001-04-01	822
2001-07-01	468
2001-10-01	-66
2002-01-01	-2356
2002-04-01	801
2002-07-01	475
2002-10-01	-1363
2003-01-01	-92
2003-04-01	1303
2003-07-01	2892
2003-10-01	2343
2004-01-01	-1075
2004-04-01	3216
2004-07-01	2668
2004-10-01	3047
2005-01-01	-1949
2005-04-01	3331
2005-07-01	1959
2005-10-01	1470
2006-01-01	-2274
2006-04-01	1919
2006-07-01	1684
2006-10-01	768
2007-01-01	-3141
2007-04-01	1434
2007-07-01	1210
2007-10-01	855
2008-01-01	-2154
2008-04-01	3414
2008-07-01	1769
2008-10-01	1727
2009-01-01	126
2009-04-01	7052
2009-07-01	3717
2009-10-01	6595
2010-01-01	6308
2010-04-01	6850
2010-07-01	5933
2010-10-01	6603
2011-01-01	5902
2011-04-01	6914
2011-07-01	5023
2011-10-01	5705
2012-01-01	4538
2012-04-01	6484
2012-07-01	5212
2012-10-01	5035
2013-01-01	2848
2013-04-01	6202
2013-07-01	5884
2013-10-01	4640
2014-01-01	2904
2014-04-01	6794
2014-07-01	3735
2014-10-01	4899
2015-01-01	1872
2015-04-01	3964
2015-07-01	2480
2015-10-01	3123
2016-01-01	3303
2016-04-01	4789
2016-07-01	3033
2016-10-01	4611
2017-01-01	1812
2017-04-01	5288
2017-07-01	4716
2017-10-01	6365
2018-01-01	4379