Year	Percent change (Units)
1980	-7.348
1981	14.900
1982	10.879
1983	9.733
1984	7.908
1985	5.201
1986	29.867
1987	7.697
1988	10.326
1989	3.968
1990	5.632
1991	13.921
1992	8.597
1993	1.810
1994	3.922
1995	-0.480
1996	2.674
1997	0.568
1998	2.868
1999	3.922
2000	4.932
2001	7.252
2002	9.988
2003	10.669
2004	11.759
2005	9.982
2006	7.246
2007	5.040
2008	9.616
2009	5.481
2010	1.674
2011	6.020
2012	3.285
2013	0.675
2014	2.286
2015	0.054
2016	-0.621
2017	7.201
2018	6.782
2019	3.286
2020	0.423
2021	1.414
2022	8.520
2023	10.171
2024	5.420
2025	4.150
2026	3.665
2027	3.272
2028	3.407
2029	3.203