Year	sq. km
1990	438.1
1991	453.5
1992	468.9
1993	484.3
1994	499.7
1995	515.1
1996	530.5
1997	545.9
1998	561.3
1999	576.7
2000	592.1
2001	598.53
2002	604.96
2003	611.39
2004	617.82
2005	624.25
2006	630.68
2007	637.11
2008	643.54
2009	649.97
2010	656.4
2011	621.96
2012	587.52
2013	553.08
2014	518.64
2015	484.2
2016	449.8
2017	449.8
2018	449.8
2019	449.8
2020	449.8
2021	449.8