Year	Number of
1990	107.48
1991	111.8
1992	116.2
1993	121.57
1994	127.93
1995	135.06
1996	141.84
1997	150.14
1998	161.04
1999	171.2
2000	176.9
2001	181.11
2002	184.06
2003	186.71
2004	187.49
2005	191.31
2006	192.34
2007	193.92
2008	196.92
2009	197.04
2010	197.07
2011	198.7
2012	199.69
2013	197.28
2014	195.87
2015	196.44
2016	198.73