Year Number of 1990 2830.39 1991 2922.64 1992 2876.59 1993 2829.59 1994 2840.76 1995 2849.34 1996 2843.82 1997 2918.39 1998 2884.98 1999 2887.95 2000 2846.82 2001 2776.02 2002 2712.24 2003 2681.12 2004 2661.24 2005 2660.52 2006 2662 2007 2652.5 2008 2583.61 2009 2550.41 2010 2426.4 2011 2392.74 2012 2390.77 2013 2336 2014 2261.05 2015 2221.13 2016 2189.32