Year	Number of
1990	206.7
1991	212.31
1992	221.45
1993	235.35
1994	247.88
1995	257.1
1996	268.96
1997	286.37
1998	300.32
1999	310.42
2000	318.86
2001	325.59
2002	330.76
2003	334.46
2004	339.53
2005	345.34
2006	355.38
2007	361.33
2008	366.69
2009	370.86
2010	370.78
2011	370.61
2012	369.79
2013	369.96
2014	369.89
2015	370.12
2016	370.91