Year	Number of
1990	86.38
1991	95.39
1992	105.37
1993	116.71
1994	129.28
1995	143.27
1996	150.8
1997	158.81
1998	167.6
1999	176.82
2000	186.5
2001	189.57
2002	192.55
2003	195.86
2004	199.18
2005	202.62
2006	205.37
2007	208.15
2008	211.47
2009	214.74
2010	218.03
2011	225.63
2012	233.51
2013	241.83
2014	250.44
2015	259.38
2016	268.78