Quarter	Millions of US Dollars
1972-10-01	45
1973-01-01	60
1973-04-01	60
1973-07-01	60
1973-10-01	60
1974-01-01	60
1974-04-01	60
1974-07-01	60
1974-10-01	60
1975-01-01	60
1975-04-01	60
1975-07-01	60
1975-10-01	60
1976-01-01	60
1976-04-01	60
1976-07-01	60
1976-10-01	60
1977-01-01	60
1977-04-01	60
1977-07-01	60
1977-10-01	60
1978-01-01	60
1978-04-01	60
1978-07-01	60
1978-10-01	60
1979-01-01	60
1979-04-01	60
1979-07-01	60
1979-10-01	60
1980-01-01	60
1980-04-01	60
1980-07-01	60
1980-10-01	60
1981-01-01	60
1981-04-01	60
1981-07-01	90
1981-10-01	90
1982-01-01	90
1982-04-01	90
1982-07-01	90
1982-10-01	140
1983-01-01	161
1983-04-01	161
1983-07-01	182
1983-10-01	183
1984-01-01	185
1984-04-01	332
1984-07-01	357
1984-10-01	360
1985-01-01	659
1985-04-01	823
1985-07-01	1152
1985-10-01	1185
1986-01-01	1217
1986-04-01	1279
1986-07-01	1367
1986-10-01	1200
1987-01-01	1510
1987-04-01	1760
1987-07-01	1725
1987-10-01	1825
1988-01-01	2050
1988-04-01	2014
1988-07-01	2039
1988-10-01	2141
1989-01-01	2508
1989-04-01	2561
1989-07-01	2642
1989-10-01	3172
1990-01-01	3191
1990-04-01	3311
1990-07-01	4067
1990-10-01	4394
1991-01-01	5443
1991-04-01	6088
1991-07-01	6339
1991-10-01	7216
1992-01-01	7422
1992-04-01	8605
1992-07-01	9419
1992-10-01	9524
1993-01-01	11004
1993-04-01	12246
1993-07-01	12865
1993-10-01	13770
1994-01-01	14271
1994-04-01	15088
1994-07-01	16435
1994-10-01	18150
1995-01-01	20337
1995-04-01	20185
1995-07-01	19032
1995-10-01	19235
1996-01-01	20745
1996-04-01	20202
1996-07-01	21395
1996-10-01	21173
1997-01-01	20053
1997-04-01	20304
1997-07-01	19341
1997-10-01	20897
1998-01-01	23909
1998-04-01	23148
1998-07-01	23619
1998-10-01	24812
1999-01-01	24941
1999-04-01	23856
1999-07-01	25489
1999-10-01	24406
2000-01-01	25446
2000-04-01	25450
2000-07-01	23980
2000-10-01	24087
2001-01-01	22510
2001-04-01	22118
2001-07-01	23850
2001-10-01	23591
2002-01-01	28082
2002-04-01	31554
2002-07-01	30945
2002-10-01	31588
2003-01-01	41774
2003-04-01	44667
2003-07-01	45886
2003-10-01	48731
2004-01-01	47255
2004-04-01	49089
2004-07-01	49336
2004-10-01	52590
2005-01-01	50398
2005-04-01	50597
2005-07-01	48893
2005-10-01	47537
2006-01-01	53854
2006-04-01	63049
2006-07-01	60866
2006-10-01	68242
2007-01-01	76608
2007-04-01	85971
2007-07-01	87501
2007-10-01	85029
2008-01-01	86428
2008-04-01	93316
2008-07-01	81466
2008-10-01	84666
2009-01-01	89008
2009-04-01	110231
2009-07-01	117818
2009-10-01	104983
2010-01-01	99710
2010-04-01	135517
2010-07-01	157679
2010-10-01	180552
2011-01-01	194481
2011-04-01	210493
2011-07-01	196160
2011-10-01	197011
2012-01-01	187208
2012-04-01	157643
2012-07-01	150195
2012-10-01	150704
2013-01-01	142803
2013-04-01	133055
2013-07-01	131113
2013-10-01	134182
2014-01-01	133099
2014-04-01	133325
2014-07-01	123501
2014-10-01	121971
2015-01-01	105444
2015-04-01	116808
2015-07-01	117288
2015-10-01	105105
2016-01-01	97062
2016-04-01	75634
2016-07-01	63760
2016-10-01	55777
2017-01-01	54268
2017-04-01	45642
2017-07-01	41228
2017-10-01	45127
2018-01-01	54147
2018-04-01	54183