Year	Number of
1990	267.34
1991	270.4
1992	270.02
1993	272.82
1994	274.27
1995	274.44
1996	276.59
1997	280.35
1998	284.49
1999	291.48
2000	291.45
2001	293.69
2002	295.69
2003	299.79
2004	307.11
2005	306.76
2006	312.12
2007	316.37
2008	321.6
2009	325.29
2010	331.01
2011	337.86
2012	346.48
2013	354.54
2014	356.11
2015	355.9
2016	357.74