Year	Percent change (Units)
1980	7.444
1981	6.942
1982	5.941
1983	6.250
1984	7.762
1985	-0.876
1986	1.153
1987	5.389
1988	9.938
1989	9.060
1990	9.007
1991	9.547
1992	8.886
1993	9.896
1994	9.211
1995	9.830
1996	10.002
1997	7.327
1998	-7.359
1999	6.131
2000	8.671
2001	0.518
2002	5.391
2003	5.789
2004	6.783
2005	4.976
2006	5.584
2007	6.299
2008	4.832
2009	-1.514
2010	7.528
2011	5.293
2012	5.474
2013	4.694
2014	6.007
2015	5.007
2016	4.450
2017	5.813
2018	4.843
2019	4.413
2020	-5.457
2021	3.298
2022	8.650
2023	3.680
2024	4.421
2025	4.395
2026	4.405
2027	3.954
2028	3.962
2029	3.966