Quarter	Percent
1987-12-31	27.6
1988-03-31	29.4
1988-06-30	38.1
1988-09-30	42.6
1988-12-31	46.8
1989-03-31	49.1
1989-06-30	45.7
1989-09-30	44.4
1989-12-31	38
1990-03-31	29.1
1990-06-30	21.1
1990-09-30	18.1
1990-12-31	15
1991-03-31	10.6
1991-06-30	2.9
1991-09-30	-5.2
1991-12-31	-8.1
1992-03-31	-11.8
1992-06-30	-8.6
1992-09-30	-8.6
1992-12-31	-7.6
1993-03-31	-9.9
1993-06-30	-11.4
1993-09-30	-9.6
1993-12-31	-14.8
1994-03-31	-14.4
1994-06-30	-13.5
1994-09-30	-13.2
1994-12-31	-11.6
1995-03-31	-7.6
1995-06-30	-3.7
1995-09-30	-3.6
1995-12-31	-6.3
1996-03-31	-5.4
1996-06-30	-10.6
1996-09-30	-11.5
1996-12-31	-12.3
1997-03-31	-11.3
1997-06-30	-8.9
1997-09-30	-10.3
1997-12-31	-5.1
1998-03-31	-0.5
1998-06-30	2.3
1998-09-30	10.2
1998-12-31	10.5
1999-03-31	11.6
1999-06-30	6.4
1999-09-30	6.3
1999-12-31	6.6
2000-03-31	12.7
2000-06-30	20.7
2000-09-30	29
2000-12-31	33.4
2001-03-31	32.6
2001-06-30	30.8
2001-09-30	25.6
2001-12-31	19.2
2002-03-31	9.9
2002-06-30	8.5
2002-09-30	7.8
2002-12-31	12.8
2003-03-31	17.3
2003-06-30	14
2003-09-30	9.8
2003-12-31	4.9
2004-03-31	5.3
2004-06-30	3.2
2004-09-30	9.2
2004-12-31	15.5
2005-03-31	16.9
2005-06-30	24.5
2005-09-30	18.4
2005-12-31	9.3
2006-03-31	7.2
2006-06-30	1
2006-09-30	13.1
2006-12-31	8.6
2007-03-31	6.7
2007-06-30	17.3
2007-09-30	14.7
2007-12-31	28.9
2008-03-31	32.8
2008-06-30	26
2008-09-30	17.1
2008-12-31	14.1
2009-03-31	4.5
2009-06-30	-2.8
2009-09-30	-7.2
2009-12-31	-13.7
2010-03-31	-16.3
2010-06-30	-12.3
2010-09-30	-13
2010-12-31	-7
2011-03-31	-7
2011-06-30	-8.2
2011-09-30	-5.1
2011-12-31	-4.5
2012-03-31	-3.9
2012-06-30	-3.1
2012-09-30	-4.7
2012-12-31	-6
2013-03-31	-5.1
2013-06-30	-6.8
2013-09-30	-5.8
2013-12-31	-8
2014-03-31	-7.6
2014-06-30	-7
2014-09-30	-5.6
2014-12-31	-6.9
2015-03-31	-6.2
2015-06-30	-4.9
2015-09-30	-6.6
2015-12-31	-6.8
2016-03-31	-4.7
2016-06-30	-3.2
2016-09-30	-0.9
2016-12-31	3
2017-03-31	3.7
2017-06-30	2.4
2017-09-30	1.6
2017-12-31	0.3
2018-03-31	-0.9
2018-06-30	-1.3
2018-09-30	-3.9
2018-12-31	-3.4
2019-03-31	-2.2
2019-06-30	-0.8
2019-09-30	1
2019-12-31	0.4
2020-03-31	8.5
2020-06-30	21.1
2020-09-30	20.6
2020-12-31	22.3
2021-03-31	9.4
2021-06-30	-4.2
2021-09-30	-7.1
2021-12-31	-6.3
2022-03-31	-4.3
2022-06-30	-5.2
2022-09-30	-4.2
2022-12-31	-7
2023-03-31	-9.2
2023-06-30	-6.5
2023-09-30	-5.1
2023-12-31	-2.3