Year Yards 1990 308.6 1991 306.8 1992 298.2 1993 310.6 1994 317.9 1995 328.9 1996 316.4 1997 314.9 1998 317.7 1999 318.8 2000 319.4 2001 317.6 2002 328.4 2003 318.3 2004 327.2 2005 315.9 2006 322.1 2007 325.2 2008 327.2 2009 335.1 2010 336 2011 346.8 2012 347.2 2013 348.5