Quarter	Millions of US Dollars
1972-10-01	30
1973-01-01	55
1973-04-01	78
1973-07-01	104
1973-10-01	97
1974-01-01	127
1974-04-01	129
1974-07-01	127
1974-10-01	138
1975-01-01	141
1975-04-01	140
1975-07-01	128
1975-10-01	130
1976-01-01	132
1976-04-01	132
1976-07-01	136
1976-10-01	139
1977-01-01	137
1977-04-01	139
1977-07-01	141
1977-10-01	153
1978-01-01	160
1978-04-01	157
1978-07-01	172
1978-10-01	175
1979-01-01	170
1979-04-01	171
1979-07-01	179
1979-10-01	178
1980-01-01	189
1980-04-01	208
1980-07-01	155
1980-10-01	145
1981-01-01	136
1981-04-01	125
1981-07-01	128
1981-10-01	129
1982-01-01	116
1982-04-01	112
1982-07-01	109
1982-10-01	135
1983-01-01	99
1983-04-01	109
1983-07-01	107
1983-10-01	105
1984-01-01	108
1984-04-01	103
1984-07-01	99
1984-10-01	97
1985-01-01	97
1985-04-01	98
1985-07-01	108
1985-10-01	138
1986-01-01	133
1986-04-01	141
1986-07-01	149
1986-10-01	151
1987-01-01	161
1987-04-01	160
1987-07-01	159
1987-10-01	183
1988-01-01	257
1988-04-01	208
1988-07-01	201
1988-10-01	212
1989-01-01	172
1989-04-01	168
1989-07-01	173
1989-10-01	177
1990-01-01	177
1990-04-01	185
1990-07-01	199
1990-10-01	241
1991-01-01	218
1991-04-01	209
1991-07-01	239
1991-10-01	255
1992-01-01	237
1992-04-01	253
1992-07-01	274
1992-10-01	139
1993-01-01	137
1993-04-01	125
1993-07-01	129
1993-10-01	91
1994-01-01	95
1994-04-01	100
1994-07-01	104
1994-10-01	103
1995-01-01	21
1995-04-01	117
1995-07-01	52
1995-10-01	20
1996-01-01	20
1996-04-01	19
1996-10-01	174
1997-01-01	461
1997-04-01	458
1997-07-01	461
1997-10-01	780
1998-01-01	833
1998-04-01	899
1998-07-01	939
1998-10-01	1471
1999-01-01	1344
1999-04-01	1543
1999-07-01	2318
1999-10-01	2230
2000-01-01	3152
2000-04-01	2403
2000-07-01	2332
2000-10-01	2321
2001-01-01	3750
2001-04-01	4135
2001-07-01	4718
2001-10-01	4324
2002-01-01	4461
2002-04-01	4912
2002-07-01	4650
2002-10-01	3653
2003-01-01	4403
2003-04-01	5485
2003-07-01	5891
2003-10-01	6022
2004-01-01	6817
2004-04-01	6411
2004-07-01	7288
2004-10-01	7795
2005-01-01	8326
2005-04-01	8797
2005-07-01	8119
2005-10-01	8286
2006-01-01	8840
2006-04-01	7677
2006-07-01	8257
2006-10-01	9343
2007-01-01	11628
2007-04-01	10494
2007-07-01	7617
2007-10-01	7468
2008-01-01	11420
2008-04-01	11928
2008-07-01	11818
2008-10-01	15633
2009-01-01	14112
2009-04-01	15931
2009-07-01	16178
2009-10-01	15639
2010-01-01	13870
2010-04-01	12147
2010-07-01	10628
2010-10-01	13515
2011-01-01	13983
2011-04-01	17428
2011-07-01	14530
2011-10-01	13247
2012-01-01	14699
2012-04-01	11287
2012-07-01	12449
2012-10-01	13918
2013-01-01	14712
2013-04-01	14502
2013-07-01	14632
2013-10-01	14758
2014-01-01	16529
2014-04-01	16649
2014-07-01	15211
2014-10-01	15100
2015-01-01	15660
2015-04-01	16602
2015-07-01	16219
2015-10-01	15647
2016-01-01	16825
2016-04-01	15265
2016-07-01	15274
2016-10-01	15254
2017-01-01	15133
2017-04-01	15523
2017-07-01	16481
2017-10-01	15707
2018-01-01	16181
2018-04-01	16402