Year	Percent change
1980	26.145
1981	17.969
1982	10.826
1983	13.964
1984	16.638
1985	1.481
1986	7.976
1987	7.717
1988	13.992
1989	11.568
1990	21.495
1991	12.186
1992	11.383
1993	11.747
1994	8.448
1995	7.675
1996	15.937
1997	9.565
1998	9.371
1999	4.692
2000	6.176
2001	14.158
2002	9.551
2003	8.969
2004	9.011
2005	10.983
2006	10.02
2007	15.842
2008	9.636
2009	3.43
2010	6.25
2011	6.723
2012	7.537
2013	6.939
2014	2.763
2015	2.237
2016	3.988
2017	6.581
2018	4.27
2019	4.5
2020	4.6
2021	4.7
2022	4.8
2023	4.95
2024	5