Year	Number of
1990	196.83
1991	197.92
1992	201.87
1993	203.8
1994	208.75
1995	212.22
1996	217.77
1997	221.14
1998	220.78
1999	224.74
2000	227.72
2001	233.08
2002	240.29
2003	246.98
2004	251.08
2005	255.84
2006	260.24
2007	261.46
2008	260.72
2009	264.22
2010	264.2
2011	269.41
2012	278.22
2013	278.89
2014	281.5
2015	282.97
2016	286.24