Year	Percent change (Units)
1980	14.088
1981	22.235
1982	20.607
1983	15.288
1984	25.139
1985	15.031
1986	7.900
1987	28.700
1988	39.900
1989	89.500
1990	64.300
1991	103.100
1992	26.700
1993	8.400
1994	12.400
1995	12.222
1996	7.092
1997	3.556
1998	4.568
1999	7.533
2000	6.112
2001	2.648
2002	5.360
2003	5.979
2004	4.670
2005	6.925
2006	6.677
2007	12.200
2008	8.102
2009	2.952
2010	4.302
2011	4.408
2012	2.391
2013	1.909
2014	0.684
2015	-0.865
2016	0.827
2017	1.944
2018	1.272
2019	2.092
2020	1.232
2021	3.321
2022	6.477
2023	4.537
2024	2.794
2025	4.563
2026	5.504
2027	5.485
2028	5.515
2029	5.652