Year	Percent change (Units)
1980	13.516
1981	10.512
1982	-0.854
1983	6.577
1984	1.179
1985	0.585
1986	2.397
1987	2.244
1988	0.478
1989	3.323
1990	3.952
1991	2.032
1992	2.020
1993	-0.336
1994	2.229
1995	0.505
1996	-2.059
1997	1.804
1998	2.700
1999	6.300
2000	6.300
2001	6.000
2002	0.200
2003	3.300
2004	3.900
2005	0.648
2006	-1.858
2007	5.324
2008	36.965
2009	31.754
2010	-2.405
2011	2.559
2012	7.110
2013	4.339
2014	1.386
2015	4.043
2016	-1.016
2017	2.858
2018	3.702
2019	1.807
2020	1.203
2021	9.770
2022	2.625
2023	-1.035
2024	-0.239
2025	2.611
2026	3.071
2027	3.458
2028	3.436
2029	3.447