Year	Percent change (Units)
1980	12.320
1981	19.716
1982	11.130
1983	9.355
1984	-3.527
1985	-1.815
1986	4.125
1987	0.054
1988	-0.151
1989	-0.951
1990	1.130
1991	0.238
1992	1.622
1993	-0.089
1994	35.259
1995	15.797
1996	4.596
1997	5.307
1998	0.975
1999	-0.053
2000	1.567
2001	5.074
2002	2.730
2003	-0.932
2004	0.677
2005	5.295
2006	1.082
2007	0.433
2008	7.690
2009	4.067
2010	0.212
2011	3.558
2012	2.639
2013	1.763
2014	0.187
2015	1.790
2016	0.857
2017	-0.215
2018	0.928
2019	0.687
2020	1.831
2021	4.548
2022	7.616
2023	5.059
2024	2.742
2025	2.042
2026	1.953
2027	2.000
2028	1.700
2029	1.700