Quarter	Millions of US Dollars
1968-07-01	40
1968-10-01	40
1969-01-01	110
1969-04-01	125
1969-07-01	125
1969-10-01	125
1970-01-01	125
1970-04-01	125
1970-07-01	125
1970-10-01	125
1971-01-01	125
1971-04-01	125
1971-07-01	125
1971-10-01	125
1972-01-01	125
1972-04-01	125
1972-07-01	203
1972-10-01	212
1973-01-01	221
1973-04-01	233
1973-07-01	277
1973-10-01	261
1974-01-01	288
1974-04-01	315
1974-07-01	413
1974-10-01	598
1975-01-01	801
1975-04-01	1012
1975-07-01	1023
1975-10-01	1084
1976-01-01	1173
1976-04-01	1422
1976-07-01	1536
1976-10-01	1592
1977-01-01	1596
1977-04-01	1682
1977-07-01	1740
1977-10-01	1948
1978-01-01	2062
1978-04-01	2106
1978-07-01	2470
1978-10-01	2509
1979-01-01	2802
1979-04-01	2970
1979-07-01	2931
1979-10-01	2883
1980-01-01	2607
1980-04-01	3041
1980-07-01	3044
1980-10-01	2934
1981-01-01	2720
1981-04-01	2476
1981-07-01	2580
1981-10-01	2814
1982-01-01	2670
1982-04-01	2573
1982-07-01	2558
1982-10-01	2872
1983-01-01	2892
1983-04-01	2786
1983-07-01	2937
1983-10-01	2969
1984-01-01	3010
1984-04-01	2859
1984-07-01	2689
1984-10-01	2772
1985-01-01	2816
1985-04-01	2861
1985-07-01	3160
1985-10-01	3385
1986-01-01	3804
1986-04-01	4469
1986-07-01	4832
1986-10-01	5221
1987-01-01	6454
1987-04-01	6839
1987-07-01	7013
1987-10-01	7854
1988-01-01	7828
1988-04-01	7849
1988-07-01	8251
1988-10-01	9284
1989-01-01	8942
1989-04-01	8818
1989-07-01	9273
1989-10-01	10297
1990-01-01	10599
1990-04-01	10885
1990-07-01	11852
1990-10-01	12642
1991-01-01	11503
1991-04-01	11304
1991-07-01	12040
1991-10-01	12864
1992-01-01	11621
1992-04-01	11991
1992-07-01	12737
1992-10-01	11547
1993-01-01	11350
1993-04-01	10958
1993-07-01	14181
1993-10-01	13994
1994-01-01	13900
1994-04-01	15365
1994-07-01	15589
1994-10-01	14896
1995-01-01	15647
1995-04-01	16453
1995-07-01	15751
1995-10-01	15516
1996-01-01	15173
1996-04-01	15363
1996-07-01	16162
1996-10-01	16461
1997-01-01	14969
1997-04-01	15324
1997-07-01	16162
1997-10-01	16018
1998-01-01	15642
1998-04-01	17755
1998-07-01	19071
1998-10-01	22675
1999-01-01	21852
1999-04-01	25208
1999-07-01	30809
1999-10-01	32078
2000-01-01	32167
2000-04-01	39648
2000-07-01	45849
2000-10-01	58274
2001-01-01	58625
2001-04-01	58059
2001-07-01	64336
2001-10-01	65721
2002-01-01	65409
2002-04-01	69302
2002-07-01	68793
2002-10-01	70424
2003-01-01	71813
2003-04-01	81832
2003-07-01	81803
2003-10-01	92553
2004-01-01	88472
2004-04-01	85454
2004-07-01	81596
2004-10-01	86174
2005-01-01	80804
2005-04-01	76520
2005-07-01	72376
2005-10-01	70321
2006-01-01	75725
2006-04-01	78730
2006-07-01	77542
2006-10-01	83391
2007-01-01	82058
2007-04-01	84272
2007-07-01	82267
2007-10-01	87760
2008-01-01	96168
2008-04-01	91487
2008-07-01	85850
2008-10-01	86289
2009-01-01	87461
2009-04-01	90238
2009-07-01	93038
2009-10-01	93242
2010-01-01	89091
2010-04-01	84789
2010-07-01	94233
2010-10-01	97179
2011-01-01	100140
2011-04-01	104211
2011-07-01	111428
2011-10-01	112816
2012-01-01	121982
2012-04-01	122048
2012-07-01	126800
2012-10-01	133692
2013-01-01	135058
2013-04-01	142960
2013-07-01	147164
2013-10-01	151513
2014-01-01	153925
2014-04-01	153579
2014-07-01	144548
2014-10-01	144970
2015-01-01	136766
2015-04-01	145033
2015-07-01	145056
2015-10-01	143355
2016-01-01	152487
2016-04-01	165411
2016-07-01	175311
2016-10-01	163941
2017-01-01	171392
2017-04-01	183502
2017-07-01	196352
2017-10-01	205901
2018-01-01	218658
2018-04-01	211715