Year	Percent change (Units)
1980	3.727
1981	-4.431
1982	-0.448
1983	3.746
1984	6.259
1985	4.538
1986	4.239
1987	5.200
1988	5.923
1989	9.292
1990	11.349
1991	14.000
1992	1.136
1993	-9.173
1994	8.633
1995	7.275
1996	4.184
1997	9.583
1998	10.445
1999	8.469
2000	11.685
2001	0.293
2002	-2.111
2003	7.320
2004	7.542
2005	6.827
2006	13.466
2007	7.052
2008	2.028
2009	-10.143
2010	13.414
2011	8.166
2012	-0.892
2013	2.433
2014	4.516
2015	5.374
2016	4.142
2017	5.442
2018	4.771
2019	2.711
2020	-5.726
2021	7.679
2022	3.763
2023	-5.924
2024	0.766
2025	3.756
2026	3.000
2027	3.340
2028	3.340
2029	3.340