Year	Number of
1990	66.08
1991	69.24
1992	73.18
1993	77.08
1994	81.68
1995	86.93
1996	92.13
1997	97.24
1998	102.5
1999	107.91
2000	113.75
2001	119.29
2002	125.32
2003	133.1
2004	141.89
2005	151.87
2006	160.85
2007	171.04
2008	183.58
2009	196.85
2010	210.74
2011	224.32
2012	238.39
2013	253.2
2014	268.46
2015	284.33
2016	300.99