Quarter	Millions of US Dollars
1972-01-01	49
1972-04-01	127
1972-07-01	156
1972-10-01	242
1973-01-01	242
1973-04-01	378
1973-07-01	416
1973-10-01	710
1974-01-01	804
1974-04-01	1167
1974-07-01	1198
1974-10-01	1270
1975-01-01	1334
1975-04-01	1392
1975-07-01	1437
1975-10-01	1437
1976-01-01	1498
1976-04-01	1554
1976-07-01	1621
1976-10-01	1788
1977-01-01	1905
1977-04-01	1956
1977-07-01	2060
1977-10-01	2128
1978-01-01	2192
1978-04-01	2321
1978-07-01	2383
1978-10-01	2553
1979-01-01	2663
1979-04-01	2738
1979-07-01	2738
1979-10-01	2753
1980-01-01	2753
1980-04-01	2753
1980-07-01	2843
1980-10-01	2883
1981-01-01	2890
1981-04-01	2905
1981-07-01	2985
1981-10-01	2985
1982-01-01	2985
1982-04-01	3060
1982-07-01	3060
1982-10-01	3060
1983-01-01	3060
1983-04-01	3085
1983-07-01	3145
1983-10-01	3035
1984-01-01	2925
1984-04-01	2917
1984-07-01	2887
1984-10-01	2872
1985-01-01	2872
1985-04-01	2737
1985-07-01	2649
1985-10-01	2306
1986-01-01	2206
1986-04-01	2127
1986-07-01	2152
1986-10-01	2025
1987-01-01	1932
1987-04-01	1790
1987-07-01	1679
1987-10-01	1594
1988-01-01	1533
1988-04-01	1412
1988-07-01	1310
1988-10-01	1227
1989-01-01	1110
1989-04-01	934
1989-07-01	934
1989-10-01	866
1990-01-01	802
1990-04-01	723
1990-07-01	581
1990-10-01	529
1991-01-01	529
1991-04-01	1478
1991-07-01	1478
1991-10-01	1478
1992-01-01	1518
1992-04-01	1521
1992-07-01	1518
1992-10-01	1512
1993-01-01	1509
1993-04-01	1511
1993-07-01	1546
1993-10-01	1546
1994-01-01	1526
1994-04-01	1226
1994-07-01	1211
1994-10-01	1211
1995-01-01	1211
1995-04-01	1211
1995-07-01	1211
1995-10-01	1322
1996-01-01	1322
1996-04-01	1322
1996-07-01	1217
1996-10-01	2017
1997-01-01	2017
1997-04-01	2092
1997-07-01	2372
1997-10-01	3261
1998-01-01	3258
1998-04-01	3361
1998-07-01	3730
1998-10-01	4281
1999-01-01	5080
1999-04-01	5485
1999-07-01	5619
1999-10-01	6369
2000-01-01	7397
2000-04-01	7579
2000-07-01	7959
2000-10-01	8361
2001-01-01	8228
2001-04-01	8916
2001-07-01	9340
2001-10-01	9433
2002-01-01	10022
2002-04-01	10260
2002-07-01	10298
2002-10-01	10832
2003-01-01	11088
2003-04-01	12120
2003-07-01	12332
2003-10-01	13257
2004-01-01	14536
2004-04-01	15510
2004-07-01	15544
2004-10-01	16302
2005-01-01	15743
2005-04-01	15239
2005-07-01	14736
2005-10-01	15446
2006-01-01	16389
2006-04-01	15833
2006-07-01	15844
2006-10-01	16744
2007-01-01	16467
2007-04-01	16655
2007-07-01	16199
2007-10-01	15573
2008-01-01	15874
2008-04-01	17799
2008-07-01	17563
2008-10-01	17459
2009-01-01	18038
2009-04-01	18058
2009-07-01	18167
2009-10-01	17553
2010-01-01	19009
2010-04-01	20423
2010-07-01	20584
2010-10-01	20634
2011-01-01	20792
2011-04-01	20405
2011-07-01	20653
2011-10-01	25383
2012-01-01	27547
2012-04-01	28215
2012-07-01	27968
2012-10-01	32906
2013-01-01	33816
2013-04-01	31944
2013-07-01	32660
2013-10-01	32381
2014-01-01	33834
2014-04-01	35318
2014-07-01	34688
2014-10-01	37751
2015-01-01	42051
2015-04-01	41439
2015-07-01	41385
2015-10-01	44010
2016-01-01	45815
2016-04-01	47669
2016-07-01	68440
2016-10-01	65848
2017-01-01	68210
2017-04-01	69288
2017-07-01	69740
2017-10-01	69820
2018-01-01	75004
2018-04-01	73367