Year	Number of
1990	1098.86
1991	1117.79
1992	1139.85
1993	1163.4
1994	1187.85
1995	1211.37
1996	1227.35
1997	1212.66
1998	1196.84
1999	1184.54
2000	1174.89
2001	1143.54
2002	1125.15
2003	1119.55
2004	1122.65
2005	1126.41
2006	1118.63
2007	1113.39
2008	1122.29
2009	1144.82
2010	1174.58
2011	1203.5
2012	1236.27
2013	1273.51
2014	1313.16
2015	1359.5
2016	1409.27