Year	Number of
1990	74.89
1991	76.45
1992	79.13
1993	77.82
1994	78.57
1995	79.83
1996	83.8
1997	84.87
1998	88.58
1999	93.38
2000	95.53
2001	97.94
2002	98.72
2003	100.22
2004	100.91
2005	102.02
2006	104.32
2007	104.18
2008	105.05
2009	108.49
2010	114.09
2011	114.02
2012	115.3
2013	116.34
2014	117.71
2015	119
2016	120.67