Quarter	Millions of US Dollars
1972-04-01	32
1972-07-01	31
1972-10-01	51
1973-01-01	55
1973-04-01	61
1973-07-01	61
1973-10-01	87
1974-01-01	89
1974-04-01	89
1974-07-01	88
1974-10-01	91
1975-01-01	93
1975-04-01	104
1975-07-01	100
1975-10-01	119
1976-01-01	121
1976-04-01	145
1976-07-01	209
1976-10-01	282
1977-01-01	344
1977-04-01	349
1977-07-01	382
1977-10-01	465
1978-01-01	506
1978-04-01	513
1978-07-01	540
1978-10-01	543
1979-01-01	552
1979-04-01	550
1979-07-01	559
1979-10-01	551
1980-01-01	524
1980-04-01	558
1980-07-01	557
1980-10-01	548
1981-01-01	607
1981-04-01	581
1981-07-01	552
1981-10-01	541
1982-01-01	518
1982-04-01	506
1982-07-01	558
1982-10-01	556
1983-01-01	486
1983-04-01	460
1983-07-01	462
1983-10-01	521
1984-01-01	525
1984-04-01	517
1984-07-01	497
1984-10-01	494
1985-01-01	498
1985-04-01	474
1985-07-01	493
1985-10-01	545
1986-01-01	474
1986-04-01	521
1986-07-01	529
1986-10-01	682
1987-01-01	742
1987-04-01	846
1987-07-01	845
1987-10-01	939
1988-01-01	1035
1988-04-01	1095
1988-07-01	1245
1988-10-01	1386
1989-01-01	1443
1989-04-01	1609
1989-07-01	2085
1989-10-01	1909
1990-01-01	2016
1990-04-01	1898
1990-07-01	1932
1990-10-01	2006
1991-01-01	1971
1991-04-01	1918
1991-07-01	1881
1991-10-01	1767
1992-01-01	1671
1992-04-01	1588
1992-07-01	1572
1992-10-01	1481
1993-01-01	1391
1993-04-01	1272
1993-07-01	1826
1993-10-01	1764
1994-01-01	1839
1994-04-01	1823
1994-07-01	1591
1994-10-01	1691
1995-01-01	1683
1995-04-01	1687
1995-07-01	1709
1995-10-01	1584
1996-01-01	1590
1996-04-01	2090
1996-07-01	1875
1996-10-01	2083
1997-01-01	2232
1997-04-01	2455
1997-07-01	3389
1997-10-01	3439
1998-01-01	3462
1998-04-01	4938
1998-07-01	5113
1998-10-01	5180
1999-01-01	6040
1999-04-01	6316
1999-07-01	7124
1999-10-01	7438
2000-01-01	7296
2000-04-01	8907
2000-07-01	9227
2000-10-01	9234
2001-01-01	8980
2001-04-01	9955
2001-07-01	12117
2001-10-01	15884
2002-01-01	16222
2002-04-01	16589
2002-07-01	16574
2002-10-01	16971
2003-01-01	17305
2003-04-01	18397
2003-07-01	19800
2003-10-01	23423
2004-01-01	23780
2004-04-01	25700
2004-07-01	28819
2004-10-01	33034
2005-01-01	36081
2005-04-01	34895
2005-07-01	37610
2005-10-01	39126
2006-01-01	39549
2006-04-01	43845
2006-07-01	45440
2006-10-01	46812
2007-01-01	49231
2007-04-01	54557
2007-07-01	54821
2007-10-01	55053
2008-01-01	55917
2008-04-01	55282
2008-07-01	55388
2008-10-01	52481
2009-01-01	49178
2009-04-01	47435
2009-07-01	49035
2009-10-01	50707
2010-01-01	51137
2010-04-01	50635
2010-07-01	55093
2010-10-01	55388
2011-01-01	59609
2011-04-01	63026
2011-07-01	63148
2011-10-01	64264
2012-01-01	74344
2012-04-01	72408
2012-07-01	80044
2012-10-01	84149
2013-01-01	88486
2013-04-01	94497
2013-07-01	103553
2013-10-01	106016
2014-01-01	109044
2014-04-01	113887
2014-07-01	121279
2014-10-01	114743
2015-01-01	111083
2015-04-01	117831
2015-07-01	113645
2015-10-01	111167
2016-01-01	114438
2016-04-01	117681
2016-07-01	122089
2016-10-01	118562
2017-01-01	125647
2017-04-01	135702
2017-07-01	143803
2017-10-01	146284
2018-01-01	158207
2018-04-01	170383