Year	Percent change (Units)
1991	208.600
1992	325.478
1993	182.976
1994	66.300
1995	53.105
1996	44.576
1997	15.898
1998	5.952
1999	9.551
2000	8.718
2001	7.547
2002	1.754
2003	4.310
2004	11.157
2005	9.665
2006	4.746
2007	17.550
2008	22.254
2009	4.147
2010	9.513
2011	10.505
2012	14.260
2013	12.000
2014	11.571
2015	2.049
2016	1.255
2017	6.320
2018	8.159
2019	5.280
2020	2.559
2021	13.872
2022	13.234
2023	7.895
2024	10.800
2025	9.500
2026	8.200
2027	7.400
2028	6.800
2029	6.800