Quarter	Percent
1987-12-31	45.3
1988-03-31	42.2
1988-06-30	11.6
1988-09-30	14.3
1988-12-31	-1.2
1989-03-31	7.1
1989-06-30	33.6
1989-09-30	22.1
1989-12-31	32.8
1990-03-31	30.8
1990-06-30	24.4
1990-09-30	17
1990-12-31	4.1
1991-03-31	-10.8
1991-06-30	-28.4
1991-09-30	-20.7
1991-12-31	-17.2
1992-03-31	-20.7
1992-06-30	-9.6
1992-09-30	-4.7
1992-12-31	-24.5
1993-03-31	-18.7
1993-06-30	-21.4
1993-09-30	-29.3
1993-12-31	14.6
1994-03-31	55.8
1994-06-30	65.9
1994-09-30	91.8
1994-12-31	38.6
1995-03-31	7
1995-06-30	-1.6
1995-09-30	-3
1995-12-31	10.3
1996-03-31	17.1
1996-06-30	-0.7
1996-09-30	9.3
1996-12-31	11.6
1997-03-31	11.8
1997-06-30	51.5
1997-09-30	86
1997-12-31	79
1998-03-31	95.2
1998-06-30	163.7
1998-09-30	14.3
1998-12-31	24.1
1999-03-31	4.6
1999-06-30	9.6
1999-09-30	11.7
1999-12-31	6.5
2000-03-31	6.5
2000-06-30	3
2000-09-30	26.7
2000-12-31	15.4
2001-03-31	13
2001-06-30	0
2001-09-30	-5.2
2001-12-31	-19.5
2002-03-31	-21.4
2002-06-30	-23.5
2002-09-30	-10.5
2002-12-31	-0.3
2003-03-31	9.2
2003-06-30	22.3
2003-09-30	18.5
2003-12-31	30.5
2004-03-31	25.1
2004-06-30	36.3
2004-09-30	35.1
2004-12-31	14.1
2005-03-31	19.2
2005-06-30	10.4
2005-09-30	-15.3
2005-12-31	14.3
2006-03-31	-14.4
2006-06-30	-11.5
2006-09-30	7.3
2006-12-31	12.9
2007-03-31	37.4
2007-06-30	30.1
2007-09-30	32
2007-12-31	14.4
2008-03-31	13.3
2008-06-30	8
2008-09-30	-1.4
2008-12-31	-8.6
2009-03-31	-5.5
2009-06-30	-12.3
2009-09-30	-14.1
2009-12-31	-16.6
2010-03-31	-18
2010-06-30	-5
2010-09-30	-8.8
2010-12-31	-6.5
2011-03-31	-2.3
2011-06-30	2.4
2011-09-30	20
2011-12-31	27
2012-03-31	19
2012-06-30	16.1
2012-09-30	-2.7
2012-12-31	-7.3
2013-03-31	17.9
2013-06-30	7.3
2013-09-30	-0.3
2013-12-31	-10.9
2014-03-31	-40.2
2014-06-30	-44.9
2014-09-30	-25.8
2014-12-31	-19.9
2015-03-31	16.3
2015-06-30	10.3
2015-09-30	-14.5
2015-12-31	-12.9
2016-03-31	-4.5
2016-06-30	30
2016-09-30	62.5
2016-12-31	69.2
2017-03-31	40.4
2017-06-30	26.9
2017-09-30	7.6
2017-12-31	1.1
2018-03-31	-2
2018-06-30	3.1
2018-09-30	10.2
2018-12-31	15.9
2019-03-31	17.5
2019-06-30	9.8
2019-09-30	24.9
2019-12-31	9.9
2020-03-31	24.7
2020-06-30	24
2020-09-30	-2.5
2020-12-31	10.9
2021-03-31	-19.3
2021-06-30	-18.8
2021-09-30	-7.5
2021-12-31	-16.6
2022-03-31	4.2
2022-06-30	4.9
2022-09-30	20.7
2022-12-31	2.6
2023-03-31	-13.8
2023-06-30	-11.3
2023-09-30	-25.7
2023-12-31	-15.5