Year	Percent change (Units)
1980	-1.080
1981	-10.314
1982	3.093
1983	-3.874
1984	-6.030
1985	9.300
1986	-5.832
1987	-2.930
1988	1.999
1989	3.135
1990	-2.153
1991	1.201
1992	0.700
1993	1.100
1994	2.200
1995	2.000
1996	1.500
1997	0.996
1998	2.500
1999	2.500
2000	0.448
2001	2.400
2002	2.377
2003	6.573
2004	3.832
2005	7.094
2006	9.116
2007	3.254
2008	8.186
2009	3.302
2010	1.448
2011	1.999
2012	2.943
2013	5.120
2014	4.906
2015	1.540
2016	5.177
2017	4.113
2018	4.378
2019	2.014
2020	2.625
2021	1.899
2022	0.065
2023	-0.300
2024	2.900
2025	4.100
2026	3.249
2027	3.249
2028	3.249
2029	3.349