Year	Percent change (Units)
1980	6.725
1981	3.523
1982	2.163
1983	0.972
1984	-1.042
1985	1.636
1986	3.320
1987	7.632
1988	5.340
1989	6.649
1990	7.859
1991	3.370
1992	3.130
1993	-0.687
1994	1.489
1995	2.307
1996	3.504
1997	4.401
1998	4.808
1999	3.907
2000	3.816
2001	1.944
2002	0.771
2003	-0.931
2004	1.789
2005	0.782
2006	1.625
2007	2.507
2008	0.319
2009	-3.122
2010	1.738
2011	-1.696
2012	-4.057
2013	-0.923
2014	0.792
2015	1.792
2016	2.019
2017	3.506
2018	2.849
2019	2.683
2020	-8.301
2021	5.737
2022	6.828
2023	2.280
2024	1.732
2025	2.066
2026	2.000
2027	1.930
2028	1.900
2029	1.900