Year	Percent change (Units)
1980	19.635
1981	4.101
1982	-13.918
1983	-10.227
1984	-9.216
1985	1.251
1986	34.971
1987	17.562
1988	2.946
1989	15.527
1990	0.401
1991	34.410
1992	-29.668
1993	62.968
1994	-1.243
1995	-17.010
1996	59.336
1997	18.047
1998	-6.485
1999	16.513
2000	5.541
2001	-14.348
2002	38.724
2003	-0.630
2004	2.377
2005	5.915
2006	3.729
2007	5.830
2008	0.244
2009	18.555
2010	25.564
2011	-2.098
2012	-16.266
2013	-6.291
2014	43.231
2015	52.419
2016	-2.261
2017	-37.880
2018	-39.587
2019	-7.656
2020	-11.827
2021	-6.355
2022	7.468
2023	39.457
2024	8.089
2025	9.898
2026	8.965
2027	1.558
2028	4.817
2029	5.110