Year	Percent change
1980	21.308
1981	9.874
1982	6.128
1983	4.913
1984	8.085
1985	-4.01
1986	10.913
1987	13.327
1988	26.723
1989	9.586
1990	14.476
1991	7.183
1992	7.601
1993	18.596
1994	16.485
1995	22.619
1996	10.396
1997	11.447
1998	-8.579
1999	8.936
2000	20.122
2001	-6.619
2002	6.008
2003	9.98
2004	22.192
2005	11.499
2006	11.145
2007	7.452
2008	10.33
2009	-10.558
2010	16.3
2011	5.275
2012	2.732
2013	5.804
2014	2.967
2015	3.618
2016	0.562
2017	6.971
2018	4.493
2019	1.042
2020	4.296
2021	4.341
2022	4.378
2023	4.346
2024	4.348