Quarter	Millions of US Dollars
1973-07-01	5
1973-10-01	5
1974-01-01	5
1974-04-01	5
1974-07-01	5
1974-10-01	6
1975-01-01	6
1975-04-01	6
1975-07-01	5
1975-10-01	5
1976-01-01	5
1976-04-01	5
1976-07-01	5
1976-10-01	6
1977-01-01	5
1977-04-01	6
1977-07-01	6
1977-10-01	16
1978-01-01	17
1978-04-01	17
1978-07-01	19
1978-10-01	19
1979-01-01	19
1979-04-01	19
1979-07-01	20
1979-10-01	20
1980-01-01	17
1980-04-01	19
1980-07-01	19
1980-10-01	18
1981-01-01	16
1981-04-01	15
1981-07-01	15
1981-10-01	16
1982-01-01	30
1982-04-01	28
1982-07-01	27
1982-10-01	29
1983-01-01	49
1983-04-01	49
1983-07-01	49
1983-10-01	48
1984-01-01	49
1984-04-01	46
1984-07-01	44
1984-10-01	42
1985-01-01	42
1985-04-01	43
1985-07-01	50
1985-10-01	109
1986-01-01	113
1986-04-01	118
1986-07-01	122
1986-10-01	122
1987-01-01	127
1987-04-01	127
1987-07-01	127
1987-10-01	140
1988-01-01	116
1988-04-01	112
1988-07-01	111
1988-10-01	114
1989-01-01	111
1989-04-01	108
1989-07-01	109
1989-10-01	100
1990-01-01	97
1990-04-01	99
1990-07-01	102
1990-10-01	103
1991-01-01	101
1991-04-01	232
1991-07-01	233
1991-10-01	236
1992-01-01	234
1992-04-01	236
1992-07-01	239
1992-10-01	236
1993-01-01	271
1993-04-01	304
1993-07-01	300
1993-10-01	331
1994-01-01	335
1994-04-01	279
1994-07-01	332
1994-10-01	331
1995-01-01	359
1995-04-01	360
1995-07-01	351
1995-10-01	349
1996-01-01	344
1996-04-01	339
1996-07-01	338
1996-10-01	333
1997-01-01	324
1997-04-01	325
1997-07-01	323
1997-10-01	319
1998-01-01	316
1998-04-01	315
1998-07-01	368
1998-10-01	399
1999-01-01	380
1999-04-01	530
1999-07-01	497
1999-10-01	512
2000-01-01	584
2000-04-01	553
2000-07-01	607
2000-10-01	594
2001-01-01	649
2001-04-01	548
2001-07-01	583
2001-10-01	620
2002-01-01	618
2002-04-01	747
2002-07-01	736
2002-10-01	761
2003-01-01	763
2003-04-01	907
2003-07-01	910
2003-10-01	954
2004-01-01	1118
2004-04-01	1121
2004-07-01	1151
2004-10-01	1254
2005-01-01	1203
2005-04-01	1139
2005-07-01	1135
2005-10-01	1114
2006-01-01	1207
2006-04-01	1211
2006-07-01	1493
2006-10-01	1531
2007-01-01	1544
2007-04-01	1848
2007-07-01	1913
2007-10-01	2040
2008-01-01	2362
2008-04-01	2127
2008-07-01	2135
2008-10-01	2106
2009-01-01	1982
2009-04-01	2057
2009-07-01	2047
2009-10-01	2042
2010-01-01	1898
2010-04-01	1803
2010-07-01	1930
2010-10-01	1977
2011-01-01	1887
2011-04-01	1943
2011-07-01	1886
2011-10-01	1798
2012-01-01	1824
2012-04-01	1750
2012-07-01	1773
2012-10-01	1743
2013-01-01	1663
2013-04-01	1679
2013-07-01	1713
2013-10-01	1754
2014-01-01	1759
2014-04-01	1708
2014-07-01	1609
2014-10-01	1505
2015-01-01	1447
2015-04-01	1384
2015-07-01	1235
2015-10-01	1277
2016-01-01	1309
2016-04-01	1251
2016-07-01	1163
2016-10-01	1280
2017-01-01	1289
2017-04-01	1103
2017-07-01	1119
2017-10-01	1127
2018-01-01	1140
2018-04-01	984