Year	Number of
1990	214.59
1991	224.82
1992	235.71
1993	247.2
1994	259.52
1995	272.97
1996	279.83
1997	287.25
1998	294.79
1999	301.55
2000	309.39
2001	317.43
2002	326.27
2003	336.36
2004	348.01
2005	361.27
2006	368.2
2007	376.64
2008	386.68
2009	397.26
2010	408.72
2011	419.96
2012	432.51
2013	446.32
2014	460.89
2015	476.57
2016	492.3