Year	Number of
1990	1081.81
1991	1079.43
1992	1093.01
1993	1108.7
1994	1141.65
1995	1159.63
1996	1181.94
1997	1203.99
1998	1231.36
1999	1273.79
2000	1285.44
2001	1288.76
2002	1291.02
2003	1282.39
2004	1241.63
2005	1243.66
2006	1289.7
2007	1322.98
2008	1334.25
2009	1369.68
2010	1408.75
2011	1424.95
2012	1447.8
2013	1481.42
2014	1513.94
2015	1546.94
2016	1586.33