Year	Number of
1990	127.98
1991	132.09
1992	136.5
1993	141.97
1994	147.86
1995	154.15
1996	160.73
1997	167.99
1998	176.63
1999	186.33
2000	192.15
2001	198.18
2002	204.13
2003	210.61
2004	218.92
2005	227.86
2006	241.47
2007	255.26
2008	273.54
2009	284.93
2010	300.07
2011	313.68
2012	324.2
2013	334.93
2014	349.26
2015	365.19
2016	382.44