Year	Percent change (Units)
1982	22.683
1983	-0.623
1984	-14.471
1985	-1.818
1986	9.180
1987	-4.185
1988	16.050
1989	15.435
1990	16.474
1991	11.238
1992	33.285
1993	27.471
1994	-4.409
1995	9.515
1996	19.344
1997	-14.760
1998	-34.224
1999	-4.962
2000	-15.445
2001	0.348
2002	39.944
2003	-17.205
2004	7.176
2005	6.070
2006	10.312
2007	26.710
2008	45.548
2009	-20.124
2010	13.071
2011	46.070
2012	9.492
2013	18.854
2014	-24.530
2015	-11.563
2016	-16.973
2017	16.646
2018	32.931
2019	14.498
2020	7.448
2021	44.828
2022	6.847
2023	-16.933
2024	-1.153
2025	2.821
2026	1.909
2027	0.655
2028	2.247
2029	2.399