Year	Number of
1990	2384.55
1991	2397.94
1992	2369.39
1993	2326.55
1994	2292.3
1995	2311.96
1996	2262.49
1997	2257.1
1998	2277.75
1999	2250.76
2000	2275.35
2001	2276.42
2002	2267.53
2003	2280.43
2004	2241.32
2005	2228.92
2006	2207.29
2007	2216.79
2008	2220.86
2009	2221.73
2010	2203.29
2011	2172.16
2012	2180.19
2013	2195.01
2014	2143.62
2015	2165.53
2016	2196.38