Year	Percent change (Units)
1981	1.833
1982	1.833
1983	1.833
1984	1.833
1985	1.833
1986	1.833
1987	1.833
1988	1.833
1989	1.833
1990	1.833
1991	175.720
1992	495.793
1993	1837.874
1994	971.954
1995	3783.921
1996	1650.825
1997	149.621
1998	134.809
1999	329.001
2000	268.350
2001	116.068
2002	105.590
2003	76.560
2004	31.013
2005	18.530
2006	12.207
2007	11.776
2008	13.170
2009	13.987
2010	15.322
2011	11.376
2012	9.042
2013	7.687
2014	7.498
2015	12.091
2016	41.125
2017	23.667
2018	18.604
2019	16.893
2020	25.103
2021	27.046
2022	13.848
2023	19.997
2024	18.036
2025	9.925
2026	7.442
2027	7.442
2028	7.442
2029	7.442