Quarter	Percent
1987-12-31	21.4
1988-03-31	25.1
1988-06-30	25.1
1988-09-30	23.1
1988-12-31	30.3
1989-03-31	32.3
1989-06-30	30.7
1989-09-30	33.7
1989-12-31	32.8
1990-03-31	28.7
1990-06-30	29.7
1990-09-30	24.3
1990-12-31	17.3
1991-03-31	11.6
1991-06-30	4.7
1991-09-30	1.6
1991-12-31	4
1992-03-31	2.9
1992-06-30	2.1
1992-09-30	1.9
1992-12-31	2.7
1993-03-31	0.3
1993-06-30	0.9
1993-09-30	1.2
1993-12-31	-1.2
1994-03-31	-1.7
1994-06-30	-1.4
1994-09-30	-0.8
1994-12-31	2.4
1995-03-31	4.6
1995-06-30	4.8
1995-09-30	7.1
1995-12-31	11.6
1996-03-31	11.3
1996-06-30	12.8
1996-09-30	13.6
1996-12-31	8.1
1997-03-31	13.4
1997-06-30	12.6
1997-09-30	12.2
1997-12-31	8.5
1998-03-31	5.7
1998-06-30	2.9
1998-09-30	-2.4
1998-12-31	-0.5
1999-03-31	-0.3
1999-06-30	3.6
1999-09-30	4.7
1999-12-31	7.3
2000-03-31	16.3
2000-06-30	30.5
2000-09-30	24.1
2000-12-31	36.9
2001-03-31	16.8
2001-06-30	2
2001-09-30	11.9
2001-12-31	2.2
2002-03-31	2.4
2002-06-30	6.9
2002-09-30	10.8
2002-12-31	11.1
2003-03-31	11.7
2003-06-30	12.5
2003-09-30	7.3
2003-12-31	8.1
2004-03-31	30.4
2004-06-30	34.9
2004-09-30	31.6
2004-12-31	35.7
2005-03-31	14.2
2005-06-30	18
2005-09-30	29.2
2005-12-31	27.5
2006-03-31	41.3
2006-06-30	29.8
2006-09-30	22.8
2006-12-31	14.3
2007-03-31	11.3
2007-06-30	13.5
2007-09-30	23.5
2007-12-31	36.6
2008-03-31	42.8
2008-06-30	41.5
2008-09-30	37.8
2008-12-31	28.6
2009-03-31	27.4
2009-06-30	18.1
2009-09-30	3.6
2009-12-31	-2
2010-03-31	-6.3
2010-06-30	-2.1
2010-09-30	-8
2010-12-31	-18.6
2011-03-31	-18.8
2011-06-30	-13.8
2011-09-30	-6.5
2011-12-31	-1
2012-03-31	-6
2012-06-30	-7.6
2012-09-30	-5
2012-12-31	9.7
2013-03-31	6.2
2013-06-30	2
2013-09-30	8.7
2013-12-31	-2.7
2014-03-31	-1.3
2014-06-30	3.8
2014-09-30	-4.9
2014-12-31	-1.3
2015-03-31	6.7
2015-06-30	-2.2
2015-09-30	0.3
2015-12-31	0.5
2016-03-31	0.6
2016-06-30	15.2
2016-09-30	16.4
2016-12-31	23.6
2017-03-31	29
2017-06-30	17.3
2017-09-30	19
2017-12-31	14.1
2018-03-31	-2.2
2018-06-30	-6.5
2018-09-30	-6.9
2018-12-31	0.9
2019-03-31	7.7
2019-06-30	7.9
2019-09-30	14.3
2019-12-31	8.6
2020-03-31	16.9
2020-06-30	22.2
2020-09-30	14.1
2020-12-31	12.1
2021-03-31	-0.4
2021-06-30	1.1
2021-09-30	-3.4
2021-12-31	3.6
2022-03-31	5.3
2022-06-30	1.6
2022-09-30	2.4
2022-12-31	-13.3
2023-03-31	-17.3
2023-06-30	-21.7
2023-09-30	-24
2023-12-31	-14