Year	Percent change (Units)
1983	-21.107
1984	9.357
1985	5.815
1986	16.540
1987	-4.239
1988	1.213
1989	-1.496
1990	16.022
1991	-1.080
1992	-13.970
1993	-35.077
1994	5.526
1995	4.720
1996	17.437
1997	-3.369
1998	3.331
1999	-3.033
2000	-9.217
2001	3.810
2002	18.210
2003	26.310
2004	-1.476
2005	2.581
2006	-1.178
2007	-2.748
2008	3.527
2009	21.106
2010	1.900
2011	16.540
2012	4.414
2013	14.189
2014	-7.897
2015	-9.172
2016	6.190
2017	1.547
2018	1.169
2019	1.687
2020	7.627
2021	-1.819
2022	6.618
2023	2.375
2024	6.357
2025	6.865
2026	9.123
2027	7.582
2028	6.562
2029	6.037