Year	Number of
1990	23943.53
1991	22966.97
1992	23186.94
1993	25776.54
1994	26855.12
1995	24716.79
1996	22350.33
1997	20568.51
1998	19822.66
1999	20632.04
2000	20640.99
2001	20354.05
2002	20262.37
2003	20065.25
2004	19403.93
2005	19144.83
2006	17827.64
2007	17268.48
2008	17158.53
2009	16266.07
2010	16050.42
2011	15409.76
2012	14849
2013	14643.08
2014	14684.74
2015	14985.71
2016	15561.86