Year	Percent change
1981	0.782
1982	3.454
1983	3.471
1984	3.488
1985	3.505
1986	3.521
1987	3.537
1988	-13.013
1989	-11.643
1990	1.493
1991	7.353
1992	-2.74
1993	0
1994	-18.232
1995	28.8
1996	5.5
1997	16
1998	-2.5
1999	3.8
2000	-3.1
2001	8.335
2002	-2.856
2003	6.704
2004	1.106
2005	3.053
2006	18.102
2007	-3.935
2008	11.813
2009	-1.773
2010	2.633
2011	1.784
2012	7.469
2013	2.087
2014	0.477
2015	4.094
2016	-0.036
2017	1.785
2018	0.897
2019	2.034
2020	2.509
2021	2.709
2022	3
2023	3
2024	3