Year	Number of
1990	333.26
1991	348.03
1992	369.13
1993	390.7
1994	409.45
1995	433.79
1996	434.04
1997	440.21
1998	446.71
1999	462.7
2000	480.83
2001	493.14
2002	505.3
2003	522.11
2004	537.01
2005	559.2
2006	575.34
2007	586.99
2008	598.36
2009	612.06
2010	622.82
2011	642.37
2012	641.44
2013	657
2014	683.6
2015	699.59
2016	720.1