Year	Percent change (Units)
1980	4.900
1981	3.900
1982	1.200
1983	-2.800
1984	4.200
1985	4.400
1986	3.094
1987	-5.972
1988	10.486
1989	0.285
1990	3.008
1991	5.113
1992	3.614
1993	2.000
1994	4.258
1995	2.253
1996	1.732
1997	4.328
1998	3.267
1999	-4.739
2000	1.092
2001	4.206
2002	4.928
2003	2.885
2004	6.832
2005	5.399
2006	4.341
2007	1.902
2008	6.565
2009	1.091
2010	4.029
2011	8.481
2012	5.783
2013	7.211
2014	4.226
2015	0.120
2016	-0.688
2017	5.970
2018	1.044
2019	0.165
2020	-9.245
2021	9.818
2022	6.186
2023	2.284
2024	0.081
2025	0.847
2026	1.990
2027	2.193
2028	2.461
2029	2.510