Year	sq. km
1990	503.1
1991	500.66
1992	498.22
1993	495.78
1994	493.34
1995	490.9
1996	488.46
1997	486.02
1998	483.58
1999	481.14
2000	478.7
2001	478.7
2002	478.7
2003	478.7
2004	478.7
2005	478.7
2006	478.7
2007	478.7
2008	478.7
2009	478.7
2010	478.7
2011	478.7
2012	478.7
2013	478.7
2014	478.7
2015	478.7
2016	478.7
2017	478.7
2018	478.7
2019	478.7
2020	478.7
2021	478.7