Year	Number of
1990	31981.75
1991	32318.01
1992	32510.27
1993	32692.25
1994	32909.27
1995	33282.41
1996	33477.56
1997	33708.22
1998	34057.31
1999	34297.52
2000	34273.54
2001	34244.7
2002	34203.46
2003	34379.37
2004	34635.6
2005	34965.98
2006	35091.56
2007	35362.26
2008	35561.84
2009	35579.22
2010	35789.23
2011	35926.16
2012	35783.39
2013	35625.11
2014	35543.1
2015	35909.68
2016	36322.24
