Year	Number of
1990	243.07
1991	242.67
1992	231.38
1993	220
1994	198.92
1995	188.1
1996	183.71
1997	178.03
1998	180.39
1999	186.94
2000	198.07
2001	206.58
2002	209.58
2003	222.66
2004	232.7
2005	233.05
2006	234.96
2007	239.15
2008	247.16
2009	255.09
2010	262.95
2011	275.14
2012	288.17
2013	280.47
2014	280.68
2015	268.37
2016	263.71