Year	Percent change (Units)
1991	5.278
1992	-4.473
1993	7.695
1994	-4.889
1995	-0.277
1996	-1.491
1997	-9.504
1998	17.667
1999	-4.125
2000	-2.774
2001	-1.483
2002	3.355
2003	0.401
2004	2.377
2005	-1.664
2006	12.638
2007	14.164
2008	8.018
2009	-24.367
2010	26.186
2011	35.800
2012	15.105
2013	-17.447
2014	14.134
2015	1.352
2016	106.903
2017	-3.916
2018	17.095
2019	-5.051
2020	82.126
2021	-24.425
2022	-15.182
2023	2.993
2024	14.095
2025	8.950
2026	1.455
2027	5.067
2028	5.627
2029	8.453