Year	Number of
1990	3980.4
1991	3908.34
1992	3871.61
1993	3837.88
1994	3755.7
1995	3752.74
1996	3671.45
1997	3555.95
1998	3500.06
1999	3444.91
2000	3381.47
2001	3328.51
2002	3304.51
2003	3277.04
2004	3170.75
2005	3144.66
2006	3100.18
2007	3114.59
2008	3159.04
2009	3160.46
2010	3199.73
2011	3240.82
2012	3292.62
2013	3320.11
2014	3322.7
2015	3365.76
2016	3417.42