Year	Number of
1990	209.16
1991	214.4
1992	224.63
1993	232.91
1994	253.21
1995	254.19
1996	245.59
1997	237.86
1998	229.97
1999	231.97
2000	225.69
2001	225.43
2002	230.78
2003	239.44
2004	243.66
2005	247.66
2006	254.1
2007	254.18
2008	248.7
2009	242.84
2010	236.55
2011	240.62
2012	237.96
2013	235.18
2014	238.69
2015	243.06
2016	247.51