Year	Percent change
1981	13.997
1982	12.495
1983	19.692
1984	20.019
1985	37.43
1986	54.8
1987	47.028
1988	54.042
1989	128.294
1990	96.008
1991	99.651
1992	180.715
1993	128.105
1994	38.355
1995	45.98
1996	35.21
1997	18.581
1998	30.567
1999	20.633
2000	30.1
2001	18.678
2002	26.654
2003	17.161
2004	17.502
2005	15.851
2006	8.239
2007	8.933
2008	16.56
2009	9.9
2010	7.9
2011	7.2
2012	7.328
2013	7.14
2014	7.862
2015	21.112
2016	7.469
2017	6.085
2018	8
2019	13.5
2020	10.5
2021	10
2022	10
2023	10
2024	10