Year	Number of
1990	134.34
1991	140.71
1992	148.14
1993	162.47
1994	178.23
1995	200.27
1996	207.94
1997	216.93
1998	223.42
1999	226.63
2000	232.9
2001	242.9
2002	251.83
2003	262.36
2004	280.65
2005	293.76
2006	300.36
2007	313.11
2008	323.91
2009	339.36
2010	351.55
2011	365.59
2012	377.01
2013	384.42
2014	402.59
2015	415.47
2016	429.57