Year	Percent change
1980	24.435
1981	18.925
1982	-10.433
1983	-0.434
1984	5.681
1985	0.919
1986	2.907
1987	9.517
1988	-39.385
1989	-7.571
1990	-4.1
1991	6.4
1992	7.7
1993	2.3
1994	7.066
1995	8.7
1996	-2.691
1997	6.799
1998	2.818
1999	2.891
2000	7.859
2001	23.099
2002	15.01
2003	7.443
2004	22.491
2005	1.565
2006	14.289
2007	2.316
2008	4.583
2009	-11.49
2010	12.461
2011	-0.857
2012	-2.239
2013	0.842
2014	6.012
2015	-7.154
2016	1.051
2017	2.293
2018	3.299
2019	5.012
2020	4.933
2021	4.733
2022	4.637
2023	4.5
2024	4.616