Year	Number of
1990	1344.75
1991	1336.65
1992	1324.54
1993	1310.54
1994	1290.3
1995	1281.52
1996	1266.56
1997	1247.69
1998	1231.85
1999	1212.24
2000	1192.29
2001	1170.62
2002	1161.54
2003	1159.35
2004	1138.26
2005	1128.31
2006	1108.69
2007	1083.96
2008	1069.12
2009	1059.23
2010	1043.54
2011	1048.37
2012	1058.63
2013	1054.11
2014	1050.75
2015	1067.22
2016	1085.18