Quarter	Millions of US Dollars
1972-01-01	31
1972-07-01	33
1974-07-01	75
1975-01-01	109
1975-04-01	139
1975-10-01	38
1976-01-01	78
1976-04-01	237
1976-07-01	300
1976-10-01	200
1977-07-01	360
1977-10-01	335
1978-01-01	584
1978-04-01	250
1978-07-01	371
1978-10-01	261
1979-01-01	298
1979-10-01	122
1980-01-01	225
1980-04-01	-50
1980-07-01	-3
1981-01-01	36
1981-04-01	53
1981-07-01	62
1981-10-01	302
1982-01-01	-121
1982-04-01	44
1982-07-01	435
1982-10-01	282
1983-01-01	60
1983-04-01	-261
1983-07-01	364
1983-10-01	396
1984-01-01	84
1984-04-01	-8
1984-07-01	108
1984-10-01	375
1985-01-01	176
1985-04-01	449
1985-07-01	284
1985-10-01	551
1986-01-01	788
1986-04-01	185
1986-07-01	-41
1986-10-01	777
1987-01-01	381
1987-04-01	311
1987-07-01	109
1987-10-01	-212
1988-01-01	-125
1988-04-01	-147
1988-10-01	-82
1989-01-01	246
1989-04-01	15
1989-07-01	-70
1989-10-01	-767
1990-01-01	-152
1990-04-01	-127
1990-07-01	-393
1990-10-01	-904
1991-01-01	-126
1991-04-01	-361
1991-07-01	63
1991-10-01	-346
1992-01-01	-152
1992-04-01	-311
1992-07-01	-978
1992-10-01	-406
1993-01-01	-340
1993-04-01	-412
1993-07-01	3088
1993-10-01	-758
1994-01-01	287
1994-04-01	-1601
1994-07-01	907
1994-10-01	2547
1995-01-01	819
1995-04-01	-467
1995-07-01	1338
1995-10-01	-1120
1996-01-01	-1424
1996-04-01	953
1996-07-01	583
1996-10-01	260
1997-01-01	1150
1997-04-01	1297
1997-07-01	-932
1997-10-01	-889
1998-01-01	-1004
1998-04-01	-276
1998-07-01	106
1998-10-01	322
1999-01-01	124
1999-04-01	-836
1999-07-01	-902
1999-10-01	-1517
2000-01-01	-283
2000-04-01	-1040
2000-07-01	444
2000-10-01	210
2001-01-01	7
2001-04-01	-912
2001-07-01	541
2001-10-01	-937
2002-01-01	535
2002-04-01	-910
2002-07-01	0
2002-10-01	976
2003-01-01	-460
2003-04-01	-726
2003-07-01	2
2003-10-01	822
2004-01-01	-145
2004-04-01	-1127
2004-07-01	1638
2004-10-01	-254
2005-01-01	778
2005-04-01	-532
2005-07-01	-1518
2005-10-01	1755
2006-01-01	-2077
2006-04-01	467
2006-07-01	-313
2006-10-01	1044
2007-01-01	-147
2007-04-01	-55
2007-07-01	1975
2007-10-01	-425
2008-01-01	-1573
2008-04-01	-677
2008-07-01	-1264
2008-10-01	2758
2009-01-01	-921
2009-04-01	1192
2009-07-01	1420
2009-10-01	-2266
2010-01-01	-654
2010-04-01	406
2010-07-01	14
2010-10-01	-433
2011-01-01	-312
2011-04-01	3099
2011-07-01	672
2011-10-01	-226
2012-01-01	-1367
2012-04-01	-2592
2012-07-01	-1009
2012-10-01	3251
2013-01-01	-1184
2013-04-01	-2601
2013-07-01	1877
2013-10-01	925
2014-01-01	-2111
2014-04-01	-2059
2014-07-01	-1559
2014-10-01	170
2015-01-01	779
2015-04-01	-1604
2015-07-01	-165
2015-10-01	786
2016-01-01	241
2016-04-01	1200
2016-07-01	-1627
2016-10-01	919
2017-01-01	-763
2017-04-01	-204
2017-07-01	-405
2017-10-01	308
2018-01-01	-629
2018-04-01	791