Quarter	Millions of US Dollars
1977-01-01	15
1982-01-01	-15
1994-01-01	10
1994-10-01	10
1995-01-01	-19
1995-04-01	13
1995-07-01	13
1995-10-01	-9
1996-01-01	5
1996-04-01	2
1996-07-01	0
1996-10-01	-5
1997-01-01	1
1997-04-01	2
1997-07-01	-1
1997-10-01	-1
1998-01-01	-16
1998-04-01	-5
1998-07-01	-1
2011-07-01	150
2012-10-01	500
2013-07-01	1000
2017-01-01	2000