Year	Number of
1990	163.46
1991	168.74
1992	174.74
1993	178.15
1994	186.5
1995	191.57
1996	198.5
1997	201.11
1998	200.15
1999	202.86
2000	209.32
2001	213.64
2002	215.46
2003	220.19
2004	227.47
2005	236.06
2006	243.5
2007	247.42
2008	248.17
2009	249.27
2010	254.68
2011	258.68
2012	269.45
2013	270.88
2014	276.75
2015	281.34
2016	286.22