Year	Number of
1990	215.16
1991	222.55
1992	218.99
1993	230.57
1994	231.17
1995	233.26
1996	222.2
1997	212.19
1998	212.08
1999	210.96
2000	211.07
2001	222.45
2002	223.02
2003	238.96
2004	243.17
2005	258.34
2006	268.9
2007	277.83
2008	289.8
2009	275.44
2010	276.61
2011	287.5
2012	297.56
2013	307.21
2014	309.1
2015	318.86
2016	327.33