Year	Percent change
1980	8.937
1981	1.328
1982	-13.463
1983	0.017
1984	-8.885
1985	-14.651
1986	0.101
1987	16.663
1988	15.847
1989	-10.725
1990	-26.733
1991	22.03
1992	3.926
1993	-8.984
1994	17.542
1995	-14.95
1996	18.902
1997	12.612
1998	-13.078
1999	-10.684
2000	-16.227
2001	-7.652
2002	-2.953
2003	-2.196
2004	6.253
2005	-12.821
2006	17.958
2007	22.886
2008	-0.696
2009	26.358
2010	15.873
2011	23.018
2012	21.899
2013	-14.534
2014	-27.806
2015	-23.568
2016	-18.367
2017	14.74
2018	-4.036
2019	22.154
2020	6.036
2021	3.152
2022	3.343
2023	2.619
2024	2.687