Year	Number of
1990	1171.79
1991	1178.79
1992	1190.42
1993	1199.03
1994	1195.66
1995	1189.4
1996	1170.64
1997	1160.21
1998	1134.37
1999	1113.92
2000	1093.21
2001	1076.35
2002	1081.56
2003	1080.81
2004	1092.34
2005	1107.95
2006	1118.75
2007	1146.04
2008	1165.24
2009	1186.86
2010	1211.43
2011	1233.47
2012	1254.62
2013	1277.99
2014	1303.11
2015	1329.93
2016	1356.22