Year	Number of
1990	77.91
1991	82.17
1992	86.69
1993	91.68
1994	96.98
1995	102.6
1996	109.43
1997	116.74
1998	124.88
1999	133.66
2000	143.18
2001	154.33
2002	166.6
2003	180.48
2004	195.3
2005	211.05
2006	225.06
2007	239.55
2008	254.71
2009	271.36
2010	289.88
2011	305.84
2012	323.44
2013	341.8
2014	360.97
2015	380.74
2016	402.25