Year	Number of
1990	31.02
1991	32.23
1992	33.48
1993	34.77
1994	36.13
1995	37.61
1996	39.62
1997	41.77
1998	44.13
1999	46.56
2000	49.05
2001	51.53
2002	54.05
2003	56.74
2004	59.61
2005	62.76
2006	65.53
2007	68.53
2008	71.83
2009	75.34
2010	79.01
2011	82.54
2012	86.23
2013	90.09
2014	94.17
2015	98.49
2016	102.8