Quarter	Millions of US Dollars
1972-10-01	50
1973-01-01	50
1973-04-01	50
1973-07-01	50
1973-10-01	50
1974-01-01	50
1974-04-01	67
1974-07-01	67
1974-10-01	67
1975-01-01	68
1975-04-01	67
1975-07-01	67
1975-10-01	67
1976-01-01	67
1976-04-01	67
1976-07-01	434
1976-10-01	446
1977-01-01	484
1977-04-01	521
1977-07-01	565
1977-10-01	574
1978-01-01	697
1978-04-01	705
1978-07-01	748
1978-10-01	829
1979-01-01	839
1979-04-01	862
1979-07-01	964
1979-10-01	950
1980-01-01	924
1980-04-01	969
1980-07-01	1044
1980-10-01	1046
1981-01-01	1026
1981-04-01	989
1981-07-01	984
1981-10-01	1062
1982-01-01	1043
1982-04-01	1029
1982-07-01	1010
1982-10-01	1060
1983-01-01	1034
1983-04-01	1029
1983-07-01	1032
1983-10-01	1034
1984-01-01	1028
1984-04-01	1002
1984-07-01	950
1984-10-01	940
1985-01-01	909
1985-04-01	911
1985-07-01	963
1985-10-01	936
1986-01-01	965
1986-04-01	1005
1986-07-01	933
1986-10-01	833
1987-01-01	870
1987-04-01	799
1987-07-01	788
1987-10-01	861
1988-01-01	742
1988-04-01	718
1988-07-01	682
1988-10-01	655
1989-01-01	582
1989-04-01	560
1989-07-01	498
1989-10-01	490
1990-01-01	468
1990-04-01	1313
1990-07-01	1250
1990-10-01	1254
1991-01-01	1248
1991-04-01	1251
1991-07-01	1258
1991-10-01	1150
1992-01-01	938
1992-04-01	942
1992-07-01	946
1992-10-01	4291
1993-01-01	4448
1993-04-01	4455
1993-07-01	4761
1993-10-01	5470
1994-01-01	5616
1994-04-01	6028
1994-07-01	6311
1994-10-01	6644
1995-01-01	6652
1995-04-01	6670
1995-07-01	7220
1995-10-01	7482
1996-01-01	7448
1996-04-01	8333
1996-07-01	9261
1996-10-01	11164
1997-01-01	12241
1997-04-01	13345
1997-07-01	14494
1997-10-01	14114
1998-01-01	14834
1998-04-01	15508
1998-07-01	15035
1998-10-01	14644
1999-01-01	15797
1999-04-01	16522
1999-07-01	17676
1999-10-01	18039
2000-01-01	19585
2000-04-01	19160
2000-07-01	19195
2000-10-01	18694
2001-01-01	17667
2001-04-01	17920
2001-07-01	17791
2001-10-01	18668
2002-01-01	20285
2002-04-01	21382
2002-07-01	21681
2002-10-01	22624
2003-01-01	23873
2003-04-01	24715
2003-07-01	25380
2003-10-01	26678
2004-01-01	26959
2004-04-01	27013
2004-07-01	27990
2004-10-01	28091
2005-01-01	29297
2005-04-01	29819
2005-07-01	30728
2005-10-01	29534
2006-01-01	32007
2006-04-01	31421
2006-07-01	32879
2006-10-01	32064
2007-01-01	33196
2007-04-01	33038
2007-07-01	32783
2007-10-01	32467
2008-01-01	33099
2008-04-01	31984
2008-07-01	31957
2008-10-01	31846
2009-01-01	32152
2009-04-01	33122
2009-07-01	34524
2009-10-01	36176
2010-01-01	37131
2010-04-01	37173
2010-07-01	38774
2010-10-01	39930
2011-01-01	41948
2011-04-01	43114
2011-07-01	42671
2011-10-01	41664
2012-01-01	43908
2012-04-01	44335
2012-07-01	44192
2012-10-01	45179
2013-01-01	45176
2013-04-01	46257
2013-07-01	45882
2013-10-01	46199
2014-01-01	46001
2014-04-01	46830
2014-07-01	46173
2014-10-01	46031
2015-01-01	48536
2015-04-01	48660
2015-07-01	49017
2015-10-01	49212
2016-01-01	50079
2016-04-01	49484
2016-07-01	49417
2016-10-01	48660
2017-01-01	47855
2017-04-01	47821
2017-07-01	49090
2017-10-01	48523
2018-01-01	52150
2018-04-01	52315