Year	Number of
1990	688.85
1991	678.34
1992	673.83
1993	665.42
1994	647.82
1995	635.71
1996	626.89
1997	614.25
1998	608.53
1999	603.76
2000	588.43
2001	582.45
2002	583.7
2003	571.16
2004	564.34
2005	552.9
2006	545.06
2007	535.87
2008	528.92
2009	527.29
2010	522.49
2011	509.62
2012	504.93
2013	497.2
2014	484.77
2015	476.31
2016	470.02