Year	Number of
1990	187.35
1991	195.23
1992	205.2
1993	215.71
1994	228.33
1995	239.51
1996	251.09
1997	265.21
1998	280.76
1999	301.7
2000	324.37
2001	348.34
2002	372.41
2003	396.44
2004	421.91
2005	445.71
2006	466.5
2007	484.5
2008	502.45
2009	519.17
2010	536.38
2011	552.77
2012	570.46
2013	589.43
2014	607.46
2015	627.44
2016	653.66