Year Square Kilometers 1990 138094.9 1991 141262.4 1992 144429.8 1993 147597.3 1994 150764.7 1995 153932.2 1996 157099.6 1997 160267.1 1998 163434.5 1999 166602 2000 169769.4 2001 170379.7 2002 170990 2003 171600.3 2004 172210.6 2005 172820.9 2006 174751.1 2007 176681.3 2008 178611.6 2009 180541.8 2010 182472 2011 182813.3 2012 183154.7 2013 183496 2014 183837.4 2015 184178.7