Year	Percent change (Units)
1986	30.698
1987	55.027
1988	66.227
1989	64.267
1990	60.425
1991	71.132
1992	65.967
1993	71.076
1994	115.700
1995	76.250
1996	80.142
1997	99.016
1998	69.634
1999	68.805
2000	38.998
2001	68.489
2002	29.705
2003	18.403
2004	9.353
2005	7.717
2006	9.653
2007	8.387
2008	10.064
2009	6.526
2010	6.401
2011	10.448
2012	6.164
2013	7.400
2014	8.170
2015	8.808
2016	8.533
2017	11.920
2018	20.302
2019	11.836
2020	14.599
2021	36.081
2022	64.270
2023	64.773
2024	45.017
2025	28.275
2026	19.563
2027	18.671
2028	18.604
2029	18.604