Quarter	Millions of US Dollars
1966-01-01	15
1966-04-01	35
1966-07-01	35
1966-10-01	35
1967-01-01	35
1967-04-01	35
1967-07-01	35
1967-10-01	35
1968-01-01	35
1968-04-01	35
1968-07-01	35
1968-10-01	35
1969-01-01	35
1969-04-01	35
1969-07-01	35
1969-10-01	35
1970-01-01	35
1970-04-01	35
1970-07-01	35
1970-10-01	35
1971-01-01	47
1971-04-01	61
1971-07-01	62
1971-10-01	62
1972-01-01	63
1972-04-01	121
1972-07-01	136
1972-10-01	136
1973-01-01	179
1973-04-01	216
1973-07-01	233
1973-10-01	217
1974-01-01	227
1974-04-01	277
1974-07-01	274
1974-10-01	290
1975-01-01	318
1975-04-01	335
1975-07-01	362
1975-10-01	369
1976-01-01	483
1976-04-01	484
1976-07-01	492
1976-10-01	579
1977-01-01	717
1977-04-01	1279
1977-07-01	1333
1977-10-01	1422
1978-01-01	1585
1978-04-01	1605
1978-07-01	2013
1978-10-01	2031
1979-01-01	1986
1979-04-01	2093
1979-07-01	2290
1979-10-01	2277
1980-01-01	2134
1980-04-01	2404
1980-07-01	2380
1980-10-01	2325
1981-01-01	2133
1981-04-01	2071
1981-07-01	2110
1981-10-01	2161
1982-01-01	2236
1982-04-01	2020
1982-07-01	1986
1982-10-01	2093
1983-01-01	1951
1983-04-01	2284
1983-07-01	2189
1983-10-01	2409
1984-01-01	2330
1984-04-01	2204
1984-07-01	2054
1984-10-01	2054
1985-01-01	2068
1985-04-01	2049
1985-07-01	2274
1985-10-01	2384
1986-01-01	2450
1986-04-01	3267
1986-07-01	3463
1986-10-01	3555
1987-01-01	4129
1987-04-01	4204
1987-07-01	4805
1987-10-01	5528
1988-01-01	6620
1988-04-01	6090
1988-07-01	6804
1988-10-01	7694
1989-01-01	8076
1989-04-01	8329
1989-07-01	9028
1989-10-01	10347
1990-01-01	10661
1990-04-01	11967
1990-07-01	14880
1990-10-01	17097
1991-01-01	15879
1991-04-01	15741
1991-07-01	17153
1991-10-01	17715
1992-01-01	18490
1992-04-01	20481
1992-07-01	21178
1992-10-01	19072
1993-01-01	18468
1993-04-01	18438
1993-07-01	19655
1993-10-01	19824
1994-01-01	20898
1994-04-01	22590
1994-07-01	23551
1994-10-01	24380
1995-01-01	27128
1995-04-01	29380
1995-07-01	31543
1995-10-01	32046
1996-01-01	32946
1996-04-01	36025
1996-07-01	38165
1996-10-01	40727
1997-01-01	39391
1997-04-01	40443
1997-07-01	40965
1997-10-01	41349
1998-01-01	44747
1998-04-01	48370
1998-07-01	47318
1998-10-01	49887
1999-01-01	48665
1999-04-01	50408
1999-07-01	58314
1999-10-01	58876
2000-01-01	56560
2000-04-01	61411
2000-07-01	61308
2000-10-01	71433
2001-01-01	80849
2001-04-01	87983
2001-07-01	98812
2001-10-01	105049
2002-01-01	109803
2002-04-01	130576
2002-07-01	121646
2002-10-01	129617
2003-01-01	135247
2003-04-01	143574
2003-07-01	153468
2003-10-01	190637
2004-01-01	188995
2004-04-01	197780
2004-07-01	200346
2004-10-01	227504
2005-01-01	233902
2005-04-01	242424
2005-07-01	263181
2005-10-01	279003
2006-01-01	294944
2006-04-01	321403
2006-07-01	341522
2006-10-01	374589
2007-01-01	387016
2007-04-01	406753
2007-07-01	436349
2007-10-01	460185
2008-01-01	479593
2008-04-01	506032
2008-07-01	471719
2008-10-01	450435
2009-01-01	430999
2009-04-01	460402
2009-07-01	490017
2009-10-01	493302
2010-01-01	478022
2010-04-01	445905
2010-07-01	471195
2010-10-01	465654
2011-01-01	486349
2011-04-01	497676
2011-07-01	474896
2011-10-01	460922
2012-01-01	493683
2012-04-01	480913
2012-07-01	495020
2012-10-01	513067
2013-01-01	519459
2013-04-01	545023
2013-07-01	562419
2013-10-01	579629
2014-01-01	592718
2014-04-01	601609
2014-07-01	575073
2014-10-01	559474
2015-01-01	558870
2015-04-01	579864
2015-07-01	600193
2015-10-01	612171
2016-01-01	635385
2016-04-01	642747
2016-07-01	658580
2016-10-01	652794
2017-01-01	668151
2017-04-01	714163
2017-07-01	756671
2017-10-01	789390
2018-01-01	818206
2018-04-01	789634