Year	Number of
1990	232.31
1991	245.08
1992	258.76
1993	273.57
1994	289.43
1995	306.46
1996	328.15
1997	351.56
1998	377.11
1999	404.77
2000	434.8
2001	467.94
2002	504.42
2003	544.65
2004	587.81
2005	633.92
2006	672.38
2007	711.6
2008	752.48
2009	796.34
2010	844.22
2011	888.42
2012	936.9
2013	988.45
2014	1042.68
2015	1099.21
2016	1159.87