Quarter	Millions of US Dollars
1969-01-01	0
1969-04-01	0
1969-07-01	0
1969-10-01	0
1970-01-01	0
1970-04-01	0
1970-07-01	0
1970-10-01	0
1971-01-01	0
1971-04-01	0
1971-07-01	0
1971-10-01	0
1972-01-01	0
1972-04-01	0
1972-07-01	0
1972-10-01	0
1973-01-01	0
1973-04-01	0
1973-07-01	0
1973-10-01	0
1974-01-01	0
1974-04-01	0
1974-07-01	0
1974-10-01	0
1975-01-01	0
1975-04-01	0
1975-07-01	0
1975-10-01	0
1976-01-01	0
1976-04-01	0
1976-07-01	0
1976-10-01	0
1977-01-01	0
1977-04-01	0
1977-07-01	0
1977-10-01	0
1978-01-01	0
1978-04-01	105
1978-07-01	444
1978-10-01	783
1979-01-01	950
1979-04-01	979
1979-07-01	720
1979-10-01	405
1980-01-01	239
1980-04-01	302
1980-07-01	496
1980-10-01	553
1981-01-01	595
1981-04-01	514
1981-07-01	341
1981-10-01	263
1982-01-01	231
1982-04-01	376
1982-07-01	460
1982-10-01	506
1983-01-01	767
1983-04-01	681
1983-07-01	654
1983-10-01	685
1984-01-01	546
1984-04-01	476
1984-07-01	580
1984-10-01	1091
1985-01-01	1199
1985-04-01	1300
1985-07-01	1425
1985-10-01	1101
1986-01-01	1873
1986-04-01	1927
1986-07-01	2492
1986-10-01	2737
1987-01-01	2240
1987-04-01	2297
1987-07-01	1999
1987-10-01	1958
1988-01-01	1939
1988-04-01	1729
1988-07-01	1395
1988-10-01	1651
1989-01-01	1746
1989-04-01	1841
1989-07-01	2538
1989-10-01	2612
1990-01-01	2597
1990-04-01	2813
1990-07-01	2294
1990-10-01	2640
1991-01-01	2276
1991-04-01	1994
1991-07-01	2351
1991-10-01	2122
1992-01-01	2312
1992-04-01	2881
1992-07-01	3438
1992-10-01	3671
1993-01-01	3542
1993-04-01	3540
1993-07-01	5892
1993-10-01	6594
1994-01-01	7282
1994-04-01	7664
1994-07-01	8540
1994-10-01	6238
1995-01-01	6825
1995-04-01	7439
1995-07-01	6985
1995-10-01	7986
1996-01-01	10006
1996-04-01	11393
1996-07-01	10012
1996-10-01	12280
1997-01-01	11819
1997-04-01	12655
1997-07-01	16427
1997-10-01	19812
1998-01-01	22879
1998-04-01	24431
1998-07-01	28723
1998-10-01	32374
1999-01-01	32615
1999-04-01	36831
1999-07-01	42596
1999-10-01	40764
2000-01-01	40942
2000-04-01	47856
2000-07-01	49460
2000-10-01	58470
2001-01-01	62072
2001-04-01	55816
2001-07-01	57074
2001-10-01	59523
2002-01-01	53805
2002-04-01	65238
2002-07-01	69747
2002-10-01	80378
2003-01-01	92635
2003-04-01	95271
2003-07-01	98221
2003-10-01	102923
2004-01-01	100827
2004-04-01	105362
2004-07-01	100343
2004-10-01	109608
2005-01-01	107576
2005-04-01	113715
2005-07-01	112604
2005-10-01	121204
2006-01-01	132987
2006-04-01	144201
2006-07-01	150189
2006-10-01	153992
2007-01-01	168691
2007-04-01	175817
2007-07-01	172799
2007-10-01	195900
2008-01-01	231735
2008-04-01	228833
2008-07-01	230535
2008-10-01	201439
2009-01-01	201298
2009-04-01	216198
2009-07-01	225089
2009-10-01	206547
2010-01-01	206989
2010-04-01	176888
2010-07-01	211690
2010-10-01	208061
2011-01-01	241310
2011-04-01	244967
2011-07-01	253759
2011-10-01	253137
2012-01-01	256700
2012-04-01	239752
2012-07-01	235525
2012-10-01	249016
2013-01-01	249323
2013-04-01	272186
2013-07-01	262263
2013-10-01	240879
2014-01-01	243582
2014-04-01	233030
2014-07-01	237422
2014-10-01	226624
2015-01-01	211904
2015-04-01	225847
2015-07-01	237333
2015-10-01	209689
2016-01-01	227654
2016-04-01	209221
2016-07-01	197325
2016-10-01	179515
2017-01-01	191626
2017-04-01	203195
2017-07-01	213886
2017-10-01	210095
2018-01-01	239457
2018-04-01	222349