Year	Percent change (Units)
1980	13.502
1981	10.378
1982	6.158
1983	3.160
1984	4.368
1985	3.528
1986	1.944
1987	3.578
1988	4.100
1989	4.791
1990	5.419
1991	4.216
1992	3.042
1993	2.970
1994	2.596
1995	2.805
1996	2.937
1997	2.338
1998	1.547
1999	2.193
2000	3.367
2001	2.817
2002	1.596
2003	2.298
2004	2.668
2005	3.366
2006	3.222
2007	2.871
2008	3.815
2009	-0.320
2010	1.637
2011	3.140
2012	2.073
2013	1.466
2014	1.615
2015	0.121
2016	1.267
2017	2.131
2018	2.439
2019	1.813
2020	1.249
2021	4.682
2022	7.992
2023	4.128
2024	2.907
2025	2.000
2026	2.059
2027	2.100
2028	2.117
2029	2.143