Year	Number of
1990	63.82
1991	65.88
1992	69.23
1993	72.27
1994	77.36
1995	80.06
1996	82.03
1997	84.94
1998	90.63
1999	95.97
2000	99.02
2001	99.91
2002	101.08
2003	104.53
2004	106.66
2005	105.86
2006	102.41
2007	100.58
2008	102.39
2009	104.87
2010	107.98
2011	108.74
2012	110.41
2013	113.85
2014	116.81
2015	119.46
2016	122.81