Year	Percent change (Units)
1980	13.518
1981	10.745
1982	6.433
1983	5.050
1984	5.992
1985	5.034
1986	1.218
1987	2.679
1988	3.433
1989	3.766
1990	4.503
1991	5.040
1992	6.501
1993	4.889
1994	4.660
1995	2.612
1996	2.582
1997	3.308
1998	2.338
1999	1.136
2000	4.858
2001	1.988
2002	2.781
2003	3.978
2004	1.896
2005	2.026
2006	2.252
2007	2.171
2008	4.384
2009	0.180
2010	2.559
2011	3.482
2012	3.088
2013	0.380
2014	-0.268
2015	-1.541
2016	-1.217
2017	0.683
2018	0.782
2019	0.545
2020	-1.098
2021	2.243
2022	8.084
2023	3.943
2024	2.312
2025	2.037
2026	2.000
2027	1.900
2028	1.900
2029	1.900