Year	Number of
1990	433.65
1991	462.51
1992	463.3
1993	523.01
1994	552
1995	552.46
1996	539.09
1997	514.62
1998	525.26
1999	519.14
2000	524.07
2001	555.43
2002	541.83
2003	565.79
2004	551.68
2005	587.51
2006	599.65
2007	617.61
2008	626.25
2009	557.33
2010	558.27
2011	558.2
2012	544.29
2013	539.45
2014	502.41
2015	510.51
2016	504.42