Year	Percent change
1980	0.887
1981	6.936
1982	-12.63
1983	26.392
1984	1.875
1985	-8.197
1986	4.205
1987	28.027
1988	33.706
1989	21.793
1990	22.037
1991	9.452
1992	5.222
1993	10.152
1994	15.724
1995	19.338
1996	1.117
1997	-7.787
1998	-24.071
1999	12.48
2000	6.92
2001	-3.418
2002	3.797
2003	13.457
2004	20.557
2005	18.422
2006	1.296
2007	3.495
2008	12.498
2009	-23.177
2010	26.723
2011	13.84
2012	6.676
2013	1.979
2014	-6.195
2015	0.261
2016	-2.491
2017	7.194
2018	8.227
2019	7.297
2020	6.553
2021	6.456
2022	6.325
2023	6.3
2024	6.115