Year	Percent change (Units)
1980	1.753
1981	-8.617
1982	4.966
1983	9.255
1984	7.278
1985	8.820
1986	-2.369
1987	1.916
1988	-3.383
1989	8.301
1990	-3.500
1991	7.557
1992	4.169
1993	12.693
1994	-7.938
1995	6.191
1996	18.291
1997	-6.037
1998	-7.520
1999	-0.070
2000	-7.250
2001	5.212
2002	-2.092
2003	8.241
2004	6.620
2005	30.779
2006	21.627
2007	2.929
2008	10.722
2009	-6.938
2010	-2.300
2011	5.736
2012	0.357
2013	1.040
2014	5.188
2015	13.641
2016	12.871
2017	15.065
2018	9.277
2019	-10.187
2020	-13.358
2021	16.579
2022	7.128
2023	-28.767
2024	12.961
2025	8.773
2026	6.026
2027	6.156
2028	5.662
2029	5.663