Year	Percent change (Units)
1980	6.300
1981	-24.800
1982	-25.000
1983	12.000
1984	15.200
1985	-4.800
1986	14.800
1987	-5.900
1988	26.300
1989	11.000
1990	1.400
1991	14.700
1992	12.500
1993	4.600
1994	11.400
1995	8.200
1996	0.900
1997	13.400
1998	15.200
1999	-25.711
2000	17.851
2001	-7.504
2002	-1.242
2003	-0.017
2004	4.950
2005	11.152
2006	2.879
2007	-1.277
2008	10.579
2009	-7.508
2010	16.074
2011	14.898
2012	-0.956
2013	-1.116
2014	-0.810
2015	-3.211
2016	2.894
2017	10.224
2018	3.462
2019	-3.522
2020	-8.058
2021	21.693
2022	-0.659
2023	6.054
2024	8.916
2025	8.121
2026	11.071
2027	7.185
2028	6.807
2029	5.802