Year	Square Kilometers
1990	520260
1991	517385
1992	514510
1993	511635
1994	508760
1995	505885
1996	503010
1997	500135
1998	497260
1999	494385
2000	491510
2001	488634
2002	485758
2003	482882
2004	480006
2005	477130
2006	476714
2007	476298
2008	475882
2009	475466
2010	475050
2011	473406
2012	471762
2013	470118
2014	468474
2015	466830