Year	Number of
1990	148.53
1991	148.1
1992	147.59
1993	151.87
1994	158.94
1995	160.7
1996	170.06
1997	173.26
1998	178.6
1999	189.88
2000	196.38
2001	204.38
2002	201.66
2003	209.11
2004	215.28
2005	209.12
2006	209.85
2007	201.45
2008	203.85
2009	200.09
2010	193.29
2011	195.36
2012	193.77
2013	190.88
2014	191.21
2015	192.25
2016	194.04
