Year Number of 1990 30500.99 1991 30986.33 1992 31383.97 1993 31747.47 1994 32111.86 1995 32459.58 1996 33016.85 1997 33630.91 1998 33957.55 1999 34177.8 2000 34393.5 2001 34535.17 2002 34720.3 2003 34854.87 2004 34958.04 2005 35454.69 2006 35718.33 2007 36083.7 2008 36473.74 2009 36873.5 2010 37447.34 2011 37875.37 2012 38332.64 2013 38640.77 2014 38779.72 2015 39192.38 2016 39594.67