Year	Percent change (Units)
1980	4.228
1981	5.000
1982	-6.900
1983	-15.700
1984	-6.500
1985	1.000
1986	-2.300
1987	14.700
1988	8.200
1989	6.500
1990	1.000
1991	6.552
1992	-7.576
1993	10.941
1994	6.440
1995	2.123
1996	10.696
1997	11.815
1998	10.369
1999	11.817
2000	0.766
2001	12.852
2002	9.668
2003	7.218
2004	8.205
2005	6.312
2006	9.911
2007	7.649
2008	6.878
2009	5.929
2010	6.680
2011	7.134
2012	7.995
2013	6.571
2014	7.703
2015	7.393
2016	4.697
2017	2.638
2018	3.485
2019	2.318
2020	-1.220
2021	2.377
2022	4.360
2023	6.013
2024	4.974
2025	4.971
2026	3.952
2027	13.117
2028	12.070
2029	8.465