Year	Number of
1990	89.76
1991	93.24
1992	97.76
1993	101.69
1994	108.14
1995	113.63
1996	118.98
1997	124.24
1998	131
1999	135.26
2000	137.69
2001	138.19
2002	138.83
2003	140.83
2004	143.96
2005	146.17
2006	151.34
2007	156.52
2008	161.99
2009	166.54
2010	171.29
2011	175.33
2012	179.38
2013	183.57
2014	189.31
2015	195.66
2016	201.97