Year	Percent change
1981	5.43
1982	5.23
1983	-0.18
1984	9.05
1985	20.47
1986	-11.82
1987	-4.66
1988	6.87
1989	11.05
1990	5.005
1991	44.996
1992	2.053
1993	4.714
1994	6.293
1995	14.835
1996	-8.999
1997	2.6
1998	2.3
1999	7.084
2000	-4.123
2001	-4.3
2002	14.002
2003	6.233
2004	7.852
2005	12.32
2006	18.519
2007	18.424
2008	39.245
2009	7.138
2010	14.564
2011	35.919
2012	15
2013	7.652
2014	7.114
2015	9.377
2016	6.152
2017	16.514
2018	10.392
2019	8
2020	8
2021	8
2022	7.999
2023	7.999
2024	7.999