Year Number of 1990 3771.22 1991 3877.98 1992 3949.77 1993 4045.21 1994 4110.42 1995 4188.62 1996 4009.29 1997 3768.53 1998 3489.13 1999 3498.2 2000 3451.17 2001 3321.96 2002 3282.39 2003 3232.92 2004 3232.52 2005 3326.51 2006 3154.4 2007 3202.8 2008 3164.63 2009 2863.82 2010 2703.01 2011 2568.9 2012 2612.83 2013 2640.37 2014 2542.32 2015 2542.46 2016 2598.16