Year	Percent change (Units)
1986	9.200
1987	1.533
1988	-12.925
1989	-4.225
1990	-3.620
1991	-5.243
1992	-8.886
1993	17.779
1994	11.880
1995	0.283
1996	7.172
1997	-1.248
1998	-8.953
1999	5.374
2000	6.054
2001	5.381
2002	-17.746
2003	-19.986
2004	-8.323
2005	-9.354
2006	-2.504
2007	-7.859
2008	-39.717
2009	-6.360
2010	62.127
2011	27.285
2012	-13.063
2013	-0.786
2014	0.932
2015	3.187
2016	5.025
2017	-28.202
2018	3.889
2019	-2.985
2020	-26.277
2021	21.623
2022	8.248
2023	33.307
2024	4.282
2025	-2.247
2026	5.033
2027	6.326
2028	6.883
2029	3.915