Year	Number of
1990	166.88
1991	172.66
1992	179
1993	185.88
1994	191.44
1995	198.42
1996	209.29
1997	217.3
1998	220.35
1999	223.59
2000	231.04
2001	231.02
2002	239.43
2003	245.78
2004	249.66
2005	255.61
2006	261.22
2007	264.37
2008	280.7
2009	267.9
2010	269.33
2011	266.78
2012	272.64
2013	279.37
2014	287.91
2015	296.71
2016	305.05