Year	Percent change (Units)
1993	-17.625
1994	-22.109
1995	-18.511
1996	6.895
1997	-20.187
1998	1.550
1999	-4.918
2000	0.469
2001	-9.930
2002	19.216
2003	13.098
2004	23.945
2005	12.802
2006	44.609
2007	35.721
2008	24.038
2009	-22.011
2010	-13.785
2011	6.002
2012	24.876
2013	13.119
2014	7.558
2015	-14.544
2016	3.336
2017	1.028
2018	7.908
2019	-0.838
2020	-23.265
2021	17.237
2022	50.285
2023	22.117
2024	4.141
2025	4.369
2026	1.846
2027	1.558
2028	0.698
2029	1.120