Year	Number of
1990	1307.38
1991	1283.23
1992	1254.58
1993	1247.93
1994	1220.4
1995	1178.84
1996	1131.08
1997	1071.27
1998	1083.36
1999	1067
2000	1047.35
2001	1079.39
2002	1095.01
2003	1057.65
2004	1049.57
2005	1035.85
2006	1023.95
2007	1021.82
2008	1032.69
2009	1042.62
2010	1048.46
2011	1081.52
2012	1122.02
2013	1127.97
2014	1128.56
2015	1153.52
2016	1179.14