Year	Percent change (Units)
1980	15.028
1981	8.058
1982	5.997
1983	6.676
1984	3.942
1985	5.380
1986	-0.394
1987	3.448
1988	9.979
1989	2.632
1990	5.223
1991	5.166
1992	1.715
1993	2.364
1994	10.604
1995	3.486
1996	2.571
1997	6.364
1998	3.553
1999	7.431
2000	9.459
2001	2.673
2002	3.591
2003	-1.691
2004	4.340
2005	5.848
2006	5.322
2007	0.654
2008	2.567
2009	-10.377
2010	6.519
2011	5.811
2012	-0.584
2013	2.362
2014	3.342
2015	4.504
2016	1.620
2017	4.194
2018	1.593
2019	6.256
2020	-0.636
2021	10.354
2022	7.104
2023	10.199
2024	7.858
2025	2.000
2026	1.900
2027	1.820
2028	1.820
2029	1.820