Year	Number of
1990	89.51
1991	90.59
1992	92.77
1993	93.84
1994	96.77
1995	99.11
1996	99.62
1997	102.43
1998	107.39
1999	114.92
2000	122.47
2001	125.37
2002	125.69
2003	123.47
2004	121.66
2005	122.88
2006	129.27
2007	135.6
2008	141.95
2009	146.43
2010	152.63
2011	154.49
2012	158.64
2013	161.07
2014	166.41
2015	170.93
2016	177.04