Year	Percent change
1980	9.4
1981	21.207
1982	100.83
1983	22.118
1984	75.649
1985	15.107
1986	17.793
1987	25.23
1988	60.2
1989	251.1
1990	585.8
1991	70.3
1992	43
1993	35.3
1994	32.2
1995	27.875
1996	19.9
1997	14.9
1998	11.8
1999	7.3
2000	10.1
2001	5.5
2002	1.9
2003	0.842
2004	3.492
2005	2.133
2006	1.033
2007	2.492
2008	4.217
2009	3.45
2010	2.583
2011	4.267
2012	3.7
2013	0.9
2014	-0.025
2015	-0.933
2016	-0.583
2017	1.975
2018	1.6
2019	1.96
2020	1.911
2021	1.982
2022	2.125
2023	2.2
2024	2.275