Year	Percent change (Units)
1980	-7.202
1981	2.284
1982	-8.810
1983	-7.777
1984	1.197
1985	0.238
1986	-4.436
1987	3.639
1988	7.401
1989	14.486
1990	47.000
1991	-2.184
1992	5.193
1993	17.037
1994	-1.597
1995	10.695
1996	12.892
1997	15.257
1998	-7.230
1999	3.606
2000	19.771
2001	3.976
2002	7.244
2003	19.577
2004	19.514
2005	15.377
2006	12.494
2007	15.460
2008	17.495
2009	-10.751
2010	5.107
2011	17.594
2012	17.475
2013	8.613
2014	5.890
2015	4.014
2016	5.702
2017	0.907
2018	-0.784
2019	-0.217
2020	-8.457
2021	1.404
2022	6.246
2023	9.928
2024	2.440
2025	3.816
2026	4.021
2027	4.346
2028	4.474
2029	4.809