Year	Percent change (Units)
1980	4.721
1981	-10.233
1982	-12.490
1983	-4.863
1984	-37.718
1985	-20.222
1986	15.243
1987	7.031
1988	6.358
1989	1.205
1990	8.984
1991	-44.754
1992	93.260
1993	15.655
1994	44.400
1995	22.230
1996	7.701
1997	-1.558
1998	8.410
1999	8.387
2000	9.311
2001	5.085
2002	4.712
2003	23.366
2004	4.559
2005	2.637
2006	16.828
2007	3.853
2008	4.358
2009	-3.728
2010	-9.422
2011	-6.211
2012	11.017
2013	10.467
2014	13.812
2015	15.653
2016	12.768
2017	8.718
2018	14.615
2019	9.218
2020	-41.076
2021	25.877
2022	36.226
2023	19.146
2024	8.492
2025	5.919
2026	5.713
2027	5.419
2028	4.958
2029	5.008