Year	Number of
1990	4844.24
1991	4826.21
1992	4811.07
1993	4779.24
1994	4729.43
1995	4691.38
1996	4595.96
1997	4543
1998	4482.82
1999	4403.01
2000	4324.25
2001	4306.15
2002	4232.88
2003	4119.76
2004	4011.4
2005	3922.33
2006	3799.88
2007	3717.39
2008	3642.36
2009	3553.71
2010	3535.59
2011	3523.27
2012	3561.65
2013	3599.17
2014	3596.89
2015	3589.16
2016	3633.54