Year	Number of
1990	311.77
1991	335.6
1992	361.54
1993	391.05
1994	423.25
1995	458.27
1996	489.81
1997	523.34
1998	560.79
1999	601.39
2000	645.43
2001	670.89
2002	698.08
2003	728.52
2004	760.61
2005	794.18
2006	834.64
2007	877.05
2008	923.12
2009	972.22
2010	1024.71
2011	1102.48
2012	1186.94
2013	1279.96
2014	1380.82
2015	1490.15
2016	1607.33