Quarter	Millions of US Dollars
1978-01-01	25
1978-04-01	73
1978-07-01	79
1978-10-01	79
1979-01-01	104
1979-04-01	183
1979-07-01	248
1979-10-01	242
1980-01-01	236
1980-04-01	296
1980-07-01	300
1980-10-01	304
1981-01-01	297
1981-04-01	284
1981-07-01	324
1981-10-01	334
1982-01-01	353
1982-04-01	346
1982-07-01	336
1982-10-01	364
1983-01-01	356
1983-04-01	355
1983-07-01	462
1983-10-01	466
1984-01-01	580
1984-04-01	482
1984-07-01	512
1984-10-01	503
1985-01-01	903
1985-04-01	946
1985-07-01	1029
1985-10-01	1362
1986-01-01	1422
1986-04-01	1416
1986-07-01	1393
1986-10-01	1376
1987-01-01	1426
1987-04-01	1422
1987-07-01	1425
1987-10-01	1542
1988-01-01	1526
1988-04-01	1402
1988-07-01	1628
1988-10-01	1708
1989-01-01	1687
1989-04-01	1674
1989-07-01	1772
1989-10-01	1770
1990-01-01	1637
1990-04-01	1397
1990-07-01	1465
1990-10-01	1410
1991-01-01	1227
1991-04-01	1217
1991-07-01	1077
1991-10-01	1081
1992-01-01	1298
1992-04-01	1282
1992-07-01	1313
1992-10-01	1264
1993-01-01	1597
1993-04-01	1728
1993-07-01	2962
1993-10-01	4033
1994-01-01	4663
1994-04-01	4832
1994-07-01	5068
1994-10-01	5297
1995-01-01	5539
1995-04-01	5821
1995-07-01	6225
1995-10-01	6669
1996-01-01	7644
1996-04-01	8591
1996-07-01	9956
1996-10-01	10805
1997-01-01	11376
1997-04-01	12688
1997-07-01	12803
1997-10-01	12449
1998-01-01	12391
1998-04-01	12353
1998-07-01	12326
1998-10-01	12731
1999-01-01	12375
1999-04-01	12484
1999-07-01	11997
1999-10-01	12102
2000-01-01	11873
2000-04-01	12043
2000-07-01	11391
2000-10-01	11200
2001-01-01	10742
2001-04-01	10699
2001-07-01	10002
2001-10-01	9299
2002-01-01	8804
2002-04-01	8649
2002-07-01	9524
2002-10-01	9304
2003-01-01	9282
2003-04-01	9127
2003-07-01	8717
2003-10-01	8310
2004-01-01	7436
2004-04-01	7927
2004-07-01	8559
2004-10-01	8924
2005-01-01	9082
2005-04-01	10436
2005-07-01	9920
2005-10-01	10052
2006-01-01	9994
2006-04-01	10512
2006-07-01	10984
2006-10-01	10444
2007-01-01	9884
2007-04-01	8815
2007-07-01	8839
2007-10-01	8622
2008-01-01	8685
2008-04-01	8476
2008-07-01	8438
2008-10-01	8164
2009-01-01	7878
2009-04-01	7948
2009-07-01	7775
2009-10-01	7613
2010-01-01	7382
2010-04-01	7096
2010-07-01	7229
2010-10-01	7147
2011-01-01	7451
2011-04-01	7007
2011-07-01	6616
2011-10-01	6587
2012-01-01	6576
2012-04-01	6565
2012-07-01	7152
2012-10-01	8909
2013-01-01	9461
2013-04-01	9233
2013-07-01	9724
2013-10-01	9336
2014-01-01	9653
2014-04-01	10660
2014-07-01	10311
2014-10-01	10145
2015-01-01	10228
2015-04-01	9486
2015-07-01	9450
2015-10-01	9408
2016-01-01	9382
2016-04-01	9711
2016-07-01	10767
2016-10-01	10706
2017-01-01	10710
2017-04-01	11287
2017-07-01	15462
2017-10-01	13169
2018-01-01	13105
2018-04-01	14310