Quarter	Millions of US Dollars
1973-10-01	25
1979-10-01	-25
1993-07-01	152
1993-10-01	12
1994-01-01	59
1994-04-01	-34
1994-07-01	52
1994-10-01	-6
1995-01-01	-5
1995-04-01	16
1995-07-01	0
1995-10-01	0
1996-01-01	0
1996-04-01	0
1996-07-01	0
1996-10-01	5
1997-01-01	225
1997-04-01	-34
1997-07-01	0
1997-10-01	-78
1998-01-01	56
1998-04-01	52
1998-07-01	5
1998-10-01	-178
1999-01-01	-12
1999-04-01	210
1999-07-01	-24
1999-10-01	-98
2000-01-01	22
2000-04-01	-29
2000-07-01	-6
2000-10-01	-6
2001-01-01	36
2001-04-01	-67
2001-07-01	-98
2002-01-01	-225
2015-10-01	649
2016-04-01	4000
2016-07-01	500
2016-10-01	2500
2017-01-01	7000
2017-04-01	2000
2018-01-01	5787
2018-04-01	74