Year Number of 1990 2617.2 1991 2682.13 1992 2751.55 1993 2827.84 1994 2908.8 1995 2995.42 1996 3078.18 1997 3163.83 1998 3257.95 1999 3354.88 2000 3455.23 2001 3525.06 2002 3606.63 2003 3702.84 2004 3811.61 2005 3935.53 2006 4057.13 2007 4179.59 2008 4308.73 2009 4444.2 2010 4589.47 2011 4765.1 2012 4953.76 2013 5155.08 2014 5370.24 2015 5599.91 2016 5854.37