Year	Number of
1990	399.07
1991	412.41
1992	399.66
1993	424.68
1994	431
1995	429.47
1996	411.48
1997	393.85
1998	391.84
1999	374.91
2000	372
2001	386.58
2002	374.75
2003	376.3
2004	371.94
2005	380.36
2006	387.45
2007	392.31
2008	391.91
2009	344.44
2010	341.37
2011	331.34
2012	310.97
2013	298.2
2014	274.18
2015	274.45
2016	271.56