Year	Percent change
1981	95.655
1982	104.804
1983	164
1984	215.279
1985	242.248
1986	79.656
1987	363.414
1988	980.221
1989	1972.91
1990	1620.97
1991	472.685
1992	1119.09
1993	2477.15
1994	916.433
1995	22.409
1996	9.564
1997	5.225
1998	1.656
1999	8.94
2000	5.974
2001	7.673
2002	12.53
2003	9.3
2004	7.601
2005	5.69
2006	3.142
2007	4.457
2008	5.902
2009	4.312
2010	5.909
2011	6.503
2012	5.839
2013	5.911
2014	6.408
2015	10.673
2016	6.288
2017	2.947
2018	3.745
2019	3.925
2020	4.028
2021	3.971
2022	3.968
2023	3.968
2024	3.969