Year	Percent change (Units)
1980	5.738
1981	4.265
1982	2.154
1983	-2.151
1984	4.129
1985	3.293
1986	6.270
1987	8.546
1988	-0.090
1989	0.258
1990	1.169
1991	-0.224
1992	-3.374
1993	1.313
1994	3.609
1995	0.117
1996	4.567
1997	5.772
1998	7.363
1999	4.024
2000	4.985
2001	4.013
2002	0.560
2003	2.143
2004	7.802
2005	6.125
2006	6.317
2007	8.455
2008	2.210
2009	-7.664
2010	-2.833
2011	1.846
2012	1.064
2013	4.552
2014	1.687
2015	4.437
2016	6.304
2017	4.195
2018	4.889
2019	1.861
2020	-6.940
2021	5.149
2022	8.881
2023	4.064
2024	1.741
2025	1.996
2026	2.183
2027	2.321
2028	2.541
2029	2.481