Year	Percent change (Units)
1980	18.482
1981	11.680
1982	13.428
1983	14.753
1984	9.798
1985	31.964
1986	30.340
1987	19.599
1988	18.246
1989	23.486
1990	19.333
1991	9.828
1992	19.937
1993	12.086
1994	8.895
1995	11.385
1996	7.349
1997	1.928
1998	4.223
1999	-1.027
2000	4.293
2001	1.418
2002	2.796
2003	2.524
2004	5.369
2005	4.260
2006	4.876
2007	4.859
2008	5.479
2009	0.080
2010	2.130
2011	5.052
2012	0.783
2013	0.786
2014	0.477
2015	1.014
2016	-0.931
2017	2.035
2018	0.438
2019	-0.009
2020	-0.080
2021	6.114
2022	7.316
2023	1.229
2024	1.700
2025	1.700
2026	1.800
2027	1.800
2028	1.800
2029	1.800