Year	Percent change
1980	14.286
1981	13.194
1982	13.804
1983	10.512
1984	12.439
1985	9.111
1986	3.38
1987	4.423
1988	3.131
1989	4.464
1990	0.721
1991	11.7
1992	9.45
1993	7.474
1994	10.671
1995	8.342
1996	3.996
1997	3.586
1998	3.719
1999	2.574
2000	-2.907
2001	-8.839
2002	-9.863
2003	-2.057
2004	1.252
2005	2.658
2006	1.465
2007	6.211
2008	10.401
2009	2.448
2010	2.458
2011	15.902
2012	6.072
2013	2.594
2014	2.433
2015	9.839
2016	25.881
2017	28.533
2018	23.089
2019	15
2020	15
2021	15
2022	15
2023	15
2024	15