Year	Percent change (Units)
1980	3.800
1981	11.400
1982	8.700
1983	3.200
1984	0.000
1985	-2.400
1986	-2.500
1987	-1.700
1988	0.200
1989	1.200
1990	1.299
1991	0.899
1992	-0.302
1993	2.599
1994	3.999
1995	3.139
1996	-0.185
1997	4.602
1998	-0.418
1999	-1.259
2000	-0.730
2001	-1.175
2002	-0.496
2003	1.679
2004	2.248
2005	2.618
2006	2.041
2007	3.252
2008	3.533
2009	2.785
2010	1.962
2011	-0.336
2012	2.756
2013	3.302
2014	2.646
2015	1.849
2016	2.789
2017	1.386
2018	2.091
2019	1.007
2020	-2.325
2021	-0.611
2022	3.635
2023	0.075
2024	1.400
2025	1.800
2026	2.053
2027	2.053
2028	2.053
2029	2.053