Year	Number of
1990	452.18
1991	465.75
1992	481.9
1993	499.56
1994	517.36
1995	534.41
1996	545.73
1997	552.05
1998	556.84
1999	562
2000	567
2001	572.7
2002	580.32
2003	587.58
2004	596.18
2005	604.93
2006	610.68
2007	616.39
2008	623.48
2009	630.35
2010	637.4
2011	642.75
2012	653.01
2013	663.78
2014	675.6
2015	688.03
2016	703.62