Year	Percent change
1980	12.5
1981	-19.7
1982	-17.5
1983	-18.1
1984	17.9
1985	-7.1
1986	16.8
1987	13.3
1988	9
1990	4.75
1991	-8.039
1992	-0.719
1993	-12.255
1994	25.674
1995	32.069
1996	2.163
1997	1.122
1998	-3.198
1999	-7.187
2000	6.759
2001	11.44
2002	-3.821
2003	1.293
2004	7.51
2005	14.733
2006	10.11
2007	17.3
2008	0.221
2009	13.55
2010	8.113
2011	13.238
2012	5.2
2013	-0.443
2014	10.379
2015	1.172
2016	-6.276
2017	8.372
2018	2.034
2019	9.64
2020	10.306
2021	9.325
2022	8.304
2023	7.176
2024	6.884