Year	sq. km
1961	133860
1962	135560
1963	137260
1964	138980
1965	140690
1966	142380
1967	144580
1968	146780
1969	148480
1970	151000
1971	153500
1972	156000
1973	158380
1974	162500
1975	165500
1976	172000
1977	171000
1978	170000
1979	169000
1980	168500
1981	167500
1982	166000
1983	165500
1984	165000
1985	164720
1986	164360
1987	161630
1988	161540
1989	161690
1990	158990
1991	157890
1992	155560
1993	154770
1994	154500
1995	153300
1996	152320
1997	152220
1998	152190
1999	150600
2000	151100
2001	151500
2002	155650
2003	154250
2004	159350
2005	158850
2006	158000
2007	157320
2008	153654.74
2009	149989.49
2010	146314.22
2011	142648.96
2012	138983.7
2013	135318.45
2014	131653.19
2015	127977.92
2016	124312.67
2017	120647.41
2018	116982.15
2019	113306.88
2020	109641.63
2021	105955.37