Year	Percent change (Units)
1982	10.268
1983	10.931
1984	5.109
1985	3.125
1986	4.040
1987	7.443
1988	8.434
1989	10.000
1990	11.616
1991	9.729
1992	9.691
1993	9.023
1994	9.483
1995	7.087
1996	6.618
1997	5.103
1998	-1.575
1999	-4.000
2000	-2.083
2001	-3.546
2002	-1.618
2003	-1.794
2004	0.304
2005	1.366
2006	2.246
2007	3.807
2008	2.116
2009	1.519
2010	2.993
2011	5.680
2012	3.625
2013	4.343
2014	4.855
2015	2.315
2016	1.185
2017	1.704
2018	2.513
2019	2.860
2020	-0.894
2021	2.405
2022	1.957
2023	2.372
2024	1.751
2025	2.422
2026	2.422
2027	2.500
2028	2.500
2029	2.500