Year	Percent change (Units)
1980	3.087
1981	-2.961
1982	-0.758
1983	2.678
1984	5.275
1985	4.034
1986	3.233
1987	4.584
1988	5.467
1989	8.592
1990	10.768
1991	12.734
1992	2.287
1993	-6.710
1994	8.267
1995	7.200
1996	4.258
1997	9.289
1998	8.921
1999	8.606
2000	11.279
2001	1.162
2002	-2.578
2003	5.602
2004	6.930
2005	6.233
2006	11.523
2007	6.489
2008	1.846
2009	-9.721
2010	12.634
2011	7.453
2012	0.541
2013	2.796
2014	3.874
2015	5.352
2016	4.378
2017	5.722
2018	4.117
2019	3.379
2020	-8.903
2021	8.760
2022	6.774
2023	-3.017
2024	2.028
2025	3.756
2026	3.000
2027	3.340
2028	3.340
2029	3.340