Year	sq. km
1961	233700
1962	235800
1963	238500
1964	241100
1965	244200
1966	247380
1967	249380
1968	252380
1969	254290
1970	257050
1971	259330
1972	261700
1973	264250
1974	266300
1975	269170
1976	271500
1977	275000
1978	279180
1979	280040
1980	289300
1981	290900
1982	291770
1983	292730
1984	293840
1985	293980
1986	294970
1987	296660
1988	297440
1989	300640
1990	303430
1991	303550
1992	306160
1993	307110
1994	309640
1995	307490
1996	309660
1997	308950
1998	309760
1999	306930
2000	306520
2001	303700
2002	302830
2003	308760
2004	300410
2005	299890
2006	299460
2007	299600
2008	299810
2009	300026
2010	299883
2011	301038
2012	304030
2013	305850
2014	300825
2015	300470
2016	308750
2017	310465.482
2018	305258.072
2019	296119.07
2020	303580
2021	302910