Year Number of 1990 3614.13 1991 3668.15 1992 3710.01 1993 3746.55 1994 3771.6 1995 3779.62 1996 3778.51 1997 3778.38 1998 3775.82 1999 3759.16 2000 3741.45 2001 3698.59 2002 3661.26 2003 3611.1 2004 3550.38 2005 3484.95 2006 3398.02 2007 3311.94 2008 3246.75 2009 3193.27 2010 3140.47 2011 3082.99 2012 3022.97 2013 2967.4 2014 2920.02 2015 2880.54 2016 2854.17