Year	Percent change
1980	23.93
1981	25.127
1982	296.791
1983	328.437
1984	2177.30
1985	8170.53
1986	64.647
1987	10.662
1988	21.505
1989	16.563
1990	18.01
1991	15.436
1992	10.462
1993	9.308
1994	8.523
1995	12.574
1996	7.949
1997	6.731
1998	4.395
1999	3.133
2000	3.412
2001	0.924
2002	2.448
2003	3.939
2004	4.621
2005	4.908
2006	2.99
2007	11.726
2008	11.847
2009	0.268
2010	7.18
2011	6.9
2012	4.546
2013	6.476
2014	5.198
2015	2.952
2016	4.001
2017	2.713
2018	1.904
2019	3.001
2020	4
2021	4
2022	4.5
2023	4.5
2024	4.5