Year	Percent change (Units)
1980	-4.447
1981	1.854
1982	-3.352
1983	3.048
1984	10.411
1985	3.369
1986	2.972
1987	6.242
1988	4.538
1989	13.143
1990	6.943
1991	0.633
1992	4.888
1993	6.798
1994	13.099
1995	14.598
1996	10.044
1997	14.817
1998	3.701
1999	8.363
2000	8.540
2001	11.284
2002	4.651
2003	-9.037
2004	-2.528
2005	17.566
2006	10.506
2007	11.622
2008	-11.426
2009	-1.525
2010	-5.720
2011	3.486
2012	5.819
2013	2.317
2014	9.144
2015	15.781
2016	6.748
2017	-1.382
2018	11.371
2019	9.150
2020	-2.508
2021	4.291
2022	26.833
2023	-3.452
2024	2.000
2025	3.000
2026	2.000
2027	2.000
2028	2.000
2029	2.000