Year	sq. km
1961	315000
1962	315000
1963	315000
1964	315000
1965	315000
1966	315000
1967	315000
1968	321770
1969	321760
1970	312000
1971	312300
1972	311770
1973	308140
1974	297800
1975	297800
1976	297800
1977	297800
1978	297800
1979	299580
1980	307200
1981	302800
1982	303600
1983	310100
1984	307800
1985	307800
1986	312800
1987	310120
1988	313000
1989	314050
1990	330470
1991	341050
1992	350000
1993	350000
1994	350000
1995	360000
1996	360000
1997	360000
1998	360000
1999	370000
2000	370000
2001	380000
2002	380000
2003	384120
2004	384720
2005	429650
2006	429890
2007	437820
2008	437820
2009	437820
2010	439820
2011	444820
2012	447820
2013	456820
2014	456820
2015	456950
2016	463950
2017	465950
2018	465950
2019	465950
2020	465950
2021	465950