Year Number of 1990 1228.78 1991 1246.9 1992 1296.57 1993 1358.25 1994 1403.48 1995 1460.21 1996 1507.28 1997 1586.9 1998 1673.62 1999 1752.5 2000 1792.43 2001 1868.71 2002 1961.39 2003 2076.75 2004 2150.22 2005 2274.37 2006 2347.46 2007 2442 2008 2588.83 2009 2736.54 2010 2810.87 2011 2882.82 2012 3021.28 2013 3215.29 2014 3345.33 2015 3396.14 2016 3431.91