Year	Percent change (Units)
1990	14.662
1991	40.000
1992	14.286
1993	31.250
1994	42.857
1995	36.667
1996	17.073
1997	18.750
1998	19.298
1999	19.118
2000	11.111
2001	11.111
2002	18.000
2003	13.559
2004	15.672
2005	7.742
2006	16.168
2007	22.165
2008	17.722
2009	10.394
2010	19.805
2011	20.596
2012	41.348
2013	19.555
2014	16.223
2015	8.352
2016	11.827
2017	8.310
2018	48.844
2019	21.992
2020	48.698
2021	34.269
2022	54.014
2023	40.000
2024	35.000
2025	30.000
2026	25.000
2027	25.000
2028	25.000
2029	25.000