Year	Number of
1990	248.49
1991	248.3
1992	245.12
1993	245.6
1994	255.64
1995	249.95
1996	238.98
1997	224.86
1998	219.7
1999	222.69
2000	215.94
2001	211.59
2002	204.99
2003	198.85
2004	196.47
2005	180.66
2006	183.77
2007	183.55
2008	184.03
2009	181
2010	180.62
2011	182.82
2012	185.55
2013	189.85
2014	198.07
2015	194.99
2016	191.54