Year	Percent change (Units)
1980	1.807
1981	-9.514
1982	7.154
1983	7.537
1984	7.278
1985	8.820
1986	-2.369
1987	1.916
1988	-3.383
1989	8.301
1990	-3.500
1991	7.704
1992	3.037
1993	13.363
1994	-5.597
1995	6.322
1996	17.584
1997	-6.618
1998	-4.092
1999	3.027
2000	-8.307
2001	5.145
2002	-1.333
2003	6.378
2004	0.355
2005	22.787
2006	21.778
2007	4.169
2008	8.519
2009	-0.456
2010	-0.811
2011	4.998
2012	-0.641
2013	1.803
2014	7.605
2015	14.470
2016	15.254
2017	14.887
2018	8.423
2019	-9.767
2020	-11.983
2021	20.195
2022	10.944
2023	-29.054
2024	13.278
2025	9.013
2026	5.838
2027	6.062
2028	5.498
2029	5.499