Quarter	Millions of US Dollars
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	8
1975-07-01	8
1975-10-01	8
1976-01-01	8
1976-04-01	8
1976-07-01	8
1976-10-01	8
1977-01-01	8
1977-04-01	0
1977-07-01	0
1977-10-01	0
1978-01-01	0
1978-04-01	0
1978-07-01	0
1978-10-01	0
1979-01-01	0
1979-04-01	0
1979-07-01	0
1979-10-01	0
1980-01-01	0
1980-04-01	0
1980-07-01	80
1980-10-01	87
1981-01-01	84
1981-04-01	106
1981-07-01	58
1981-10-01	56
1982-01-01	52
1982-04-01	24
1982-07-01	64
1982-10-01	140
1983-01-01	184
1983-04-01	182
1983-07-01	457
1983-10-01	370
1984-01-01	353
1984-04-01	377
1984-07-01	61
1984-10-01	143
1985-01-01	175
1985-04-01	236
1985-07-01	300
1985-10-01	424
1986-01-01	800
1986-04-01	1089
1986-07-01	1596
1986-10-01	2264
1987-01-01	2418
1987-04-01	2040
1987-07-01	1720
1987-10-01	926
1988-01-01	746
1988-04-01	1056
1988-07-01	1207
1988-10-01	1555
1989-01-01	1285
1989-04-01	1088
1989-07-01	1118
1989-10-01	1156
1990-01-01	2191
1990-04-01	2517
1990-07-01	2726
1990-10-01	3205
1991-01-01	2889
1991-04-01	3009
1991-07-01	3474
1991-10-01	4361
1992-01-01	4275
1992-04-01	5000
1992-07-01	5239
1992-10-01	4097
1993-01-01	4290
1993-04-01	5218
1993-07-01	7791
1993-10-01	7554
1994-01-01	7382
1994-04-01	5243
1994-07-01	6637
1994-10-01	6314
1995-01-01	9497
1995-04-01	11583
1995-07-01	11967
1995-10-01	12553
1996-01-01	11831
1996-04-01	10782
1996-07-01	7439
1996-10-01	11164
1997-01-01	10176
1997-04-01	11313
1997-07-01	12951
1997-10-01	12878
1998-01-01	13593
1998-04-01	13204
1998-07-01	12359
1998-10-01	15352
1999-01-01	13969
1999-04-01	12927
1999-07-01	15725
1999-10-01	13832
2000-01-01	15567
2000-04-01	17549
2000-07-01	16053
2000-10-01	20853
2001-01-01	23126
2001-04-01	23674
2001-07-01	22092
2001-10-01	18030
2002-01-01	14962
2002-04-01	16409
2002-07-01	15969
2002-10-01	18582
2003-01-01	24584
2003-04-01	27768
2003-07-01	26643
2003-10-01	28151
2004-01-01	32258
2004-04-01	29200
2004-07-01	31673
2004-10-01	34331
2005-01-01	28597
2005-04-01	25455
2005-07-01	36062
2005-10-01	32373
2006-01-01	38169
2006-04-01	38751
2006-07-01	35020
2006-10-01	39771
2007-01-01	43248
2007-04-01	41485
2007-07-01	43358
2007-10-01	50578
2008-01-01	53695
2008-04-01	58141
2008-07-01	52624
2008-10-01	43138
2009-01-01	54116
2009-04-01	52021
2009-07-01	47789
2009-10-01	45939
2010-01-01	46159
2010-04-01	38854
2010-07-01	55552
2010-10-01	59043
2011-01-01	67379
2011-04-01	66329
2011-07-01	58905
2011-10-01	47801
2012-01-01	59135
2012-04-01	55962
2012-07-01	49980
2012-10-01	49781
2013-01-01	47777
2013-04-01	61376
2013-07-01	68362
2013-10-01	69772
2014-01-01	49346
2014-04-01	39760
2014-07-01	38981
2014-10-01	39963
2015-01-01	47384
2015-04-01	46641
2015-07-01	44333
2015-10-01	53006
2016-01-01	55454
2016-04-01	52785
2016-07-01	57580
2016-10-01	49055
2017-01-01	47219
2017-04-01	46255
2017-07-01	44504
2017-10-01	45589
2018-01-01	49696
2018-04-01	43519