Year	Number of
1990	1019.07
1991	1049.03
1992	1075.79
1993	1106.35
1994	1151.28
1995	1202.38
1996	1236.63
1997	1258.22
1998	1297.46
1999	1329.57
2000	1367.73
2001	1386.37
2002	1412
2003	1438.29
2004	1455.04
2005	1464.23
2006	1466.65
2007	1475.15
2008	1471.8
2009	1481.38
2010	1494.61
2011	1489.72
2012	1478.36
2013	1459.21
2014	1454.01
2015	1436.41
2016	1425.76