Year Number of 1990 210.06 1991 215.29 1992 221.4 1993 228.16 1994 235.39 1995 243.04 1996 249.34 1997 255.79 1998 262.33 1999 269.01 2000 276.02 2001 280.9 2002 286.06 2003 291.47 2004 297.14 2005 303.34 2006 308.3 2007 313.75 2008 320 2009 326.76 2010 334.1 2011 341.45 2012 349.38 2013 357.76 2014 366.89 2015 376.87 2016 387.13