Year	sq. km
1961	11467.6
1962	11447.6
1963	11447.6
1964	11417.6
1965	11417.6
1966	11387.6
1967	11387.6
1968	11367.6
1969	11367.6
1970	11347.6
1971	11347.6
1972	11347.6
1973	11347.6
1974	11347.6
1975	11347.6
1976	11347.6
1977	11397.6
1978	11397.6
1979	11397.6
1980	11397.6
1981	11397.6
1982	11437.6
1983	11487.6
1984	11497.6
1985	11517.6
1986	11607.6
1987	11667.6
1988	11637.6
1989	11637.6
1990	10637.6
1991	10940.2
1992	11239.202
1993	11539.883999999998
1994	11840.681999999999
1995	12145.122
1996	12452.218
1997	12754.76
1998	13067.416000000001
1999	13367.4
2000	13671.162
2001	13972.93
2002	14275.723
2003	14578.479
2004	14881.04
2005	15179.628999999999
2006	15478.003999999999
2007	15771.809
2008	16072.218
2009	16371.311000000002
2010	16670.346
2011	16966.591
2012	17266.362
2013	17565.513
2014	17863.733
2015	18164.532
2016	18464.827
2017	18766.883
2018	19069.038
2019	19230.4
2020	19230.4
2021	19230.4