Year	Number of
1990	11623.73
1991	12225.88
1992	12874.83
1993	13563.47
1994	14278.17
1995	15055.37
1996	15694.53
1997	16350.97
1998	17014.8
1999	17645.09
2000	18340.07
2001	18734.6
2002	19109.72
2003	19496.94
2004	19859.46
2005	20268.95
2006	20585.91
2007	20865
2008	21161.72
2009	21429.51
2010	21751.85
2011	22155.91
2012	22521.71
2013	22917.15
2014	23331.95
2015	23744.45
2016	24183.99