Year	Number of
1990	249.85
1991	257.78
1992	269.75
1993	295.46
1994	310.06
1995	293.95
1996	268.86
1997	267.88
1998	281.71
1999	280.62
2000	281.37
2001	303.01
2002	311
2003	312.51
2004	320.11
2005	339.28
2006	350.43
2007	352.17
2008	342.05
2009	333.42
2010	331.28
2011	328.43
2012	332.89
2013	326.01
2014	325.93
2015	324.67
2016	326.07