Year	Percent change (Units)
1984	4.390
1985	4.336
1986	5.290
1987	2.990
1988	7.549
1989	1.810
1990	8.890
1991	5.693
1992	4.969
1993	4.813
1994	6.528
1995	18.703
1996	5.282
1997	5.331
1998	21.813
1999	13.197
2000	9.971
2001	10.352
2002	14.815
2003	8.438
2004	2.377
2005	4.720
2006	-0.945
2007	3.242
2008	11.249
2009	5.672
2010	4.894
2011	4.366
2012	5.816
2013	2.893
2014	6.654
2015	6.327
2016	6.612
2017	4.700
2018	4.800
2019	2.735
2020	5.141
2021	5.694
2022	3.412
2023	3.450
2024	4.981
2025	4.800
2026	4.800
2027	4.600
2028	4.500
2029	4.500