Quarter	Millions of US Dollars
1971-01-01	58
1971-04-01	111
1971-07-01	114
1971-10-01	135
1972-01-01	276
1972-04-01	288
1972-07-01	357
1972-10-01	471
1973-01-01	558
1973-04-01	721
1973-07-01	761
1973-10-01	832
1974-01-01	872
1974-04-01	867
1974-07-01	892
1974-10-01	983
1975-01-01	1128
1975-04-01	1363
1975-07-01	1411
1975-10-01	1519
1976-01-01	1575
1976-04-01	1654
1976-07-01	2061
1976-10-01	2260
1977-01-01	2344
1977-04-01	2499
1977-07-01	3081
1977-10-01	3711
1978-01-01	4218
1978-04-01	4563
1978-07-01	5070
1978-10-01	5408
1979-01-01	5558
1979-04-01	5567
1979-07-01	5998
1979-10-01	6040
1980-01-01	5660
1980-04-01	6061
1980-07-01	6048
1980-10-01	5862
1981-01-01	5701
1981-04-01	5794
1981-07-01	6301
1981-10-01	6990
1982-01-01	7002
1982-04-01	7072
1982-07-01	6788
1982-10-01	7188
1983-01-01	7239
1983-04-01	7228
1983-07-01	7200
1983-10-01	6992
1984-01-01	7105
1984-04-01	6990
1984-07-01	6758
1984-10-01	6653
1985-01-01	7240
1985-04-01	7730
1985-07-01	8204
1985-10-01	7870
1986-01-01	8148
1986-04-01	8367
1986-07-01	8665
1986-10-01	8426
1987-01-01	8522
1987-04-01	8403
1987-07-01	8363
1987-10-01	8642
1988-01-01	8316
1988-04-01	7627
1988-07-01	7135
1988-10-01	7094
1989-01-01	6776
1989-04-01	6458
1989-07-01	6301
1989-10-01	6637
1990-01-01	7795
1990-04-01	7980
1990-07-01	8523
1990-10-01	9208
1991-01-01	9124
1991-04-01	10494
1991-07-01	11240
1991-10-01	13443
1992-01-01	14046
1992-04-01	15577
1992-07-01	17398
1992-10-01	18851
1993-01-01	19521
1993-04-01	22530
1993-07-01	29716
1993-10-01	37126
1994-01-01	42099
1994-04-01	45068
1994-07-01	47592
1994-10-01	48891
1995-01-01	47088
1995-04-01	48129
1995-07-01	50937
1995-10-01	53146
1996-01-01	56091
1996-04-01	62012
1996-07-01	65251
1996-10-01	75359
1997-01-01	79375
1997-04-01	88058
1997-07-01	97483
1997-10-01	98906
1998-01-01	101906
1998-04-01	106224
1998-07-01	106381
1998-10-01	106495
1999-01-01	105280
1999-04-01	107882
1999-07-01	109230
1999-10-01	108741
2000-01-01	111599
2000-04-01	112207
2000-07-01	112536
2000-10-01	109118
2001-01-01	109079
2001-04-01	110370
2001-07-01	111671
2001-10-01	111827
2002-01-01	111547
2002-04-01	114230
2002-07-01	111633
2002-10-01	114054
2003-01-01	115949
2003-04-01	116483
2003-07-01	118795
2003-10-01	121308
2004-01-01	125258
2004-04-01	125582
2004-07-01	125247
2004-10-01	126773
2005-01-01	127695
2005-04-01	127862
2005-07-01	133218
2005-10-01	136749
2006-01-01	142349
2006-04-01	145761
2006-07-01	151423
2006-10-01	160341
2007-01-01	162865
2007-04-01	183789
2007-07-01	186939
2007-10-01	194920
2008-01-01	196538
2008-04-01	199344
2008-07-01	200445
2008-10-01	194430
2009-01-01	191818
2009-04-01	199913
2009-07-01	218835
2009-10-01	236893
2010-01-01	245525
2010-04-01	256986
2010-07-01	267205
2010-10-01	283391
2011-01-01	301780
2011-04-01	318111
2011-07-01	320119
2011-10-01	337167
2012-01-01	352065
2012-04-01	359500
2012-07-01	380464
2012-10-01	398448
2013-01-01	413692
2013-04-01	438097
2013-07-01	454375
2013-10-01	478810
2014-01-01	487081
2014-04-01	509613
2014-07-01	513578
2014-10-01	526073
2015-01-01	526829
2015-04-01	550729
2015-07-01	549402
2015-10-01	545376
2016-01-01	567940
2016-04-01	568923
2016-07-01	576782
2016-10-01	582967
2017-01-01	594072
2017-04-01	605909
2017-07-01	628782
2017-10-01	639518
2018-01-01	649526
2018-04-01	652536