Year	Percent change
1980	0
1981	-5.104
1982	8.023
1983	19.674
1984	38.975
1985	-9.048
1986	-27.784
1987	8.431
1988	1.932
1989	-9.295
1990	5.538
1991	5.261
1992	-1.91
1993	-1.201
1994	-23.938
1995	125.542
1996	-18.317
1997	11.595
1998	8.344
1999	2.125
2000	5.394
2001	-4.071
2002	12.851
2003	112.44
2004	271.684
2005	1.511
2006	-8.059
2007	-3.799
2008	-9.173
2009	-0.077
2010	-5.485
2011	-3.054
2012	-8.085
2013	-12.928
2014	5.948
2015	29.224
2016	-3.907
2017	-15.084
2018	7.479
2019	11.145
2020	15.532
2021	7.546
2022	10.074
2023	4.483
2024	3.304