Year	Number of
1990	308.14
1991	317.1
1992	328.03
1993	339.13
1994	346.36
1995	352.36
1996	354.27
1997	358.69
1998	359.65
1999	362.04
2000	363.43
2001	365.66
2002	376.71
2003	382.86
2004	395.37
2005	410.45
2006	422.14
2007	441.62
2008	458.39
2009	476.09
2010	493.1
2011	508.79
2012	525.66
2013	542.91
2014	562.06
2015	581.93
2016	599.74