Year	sq. km
1961	2975436.6
1962	2980116.6
1963	2983536.6
1964	2987026.6
1965	2991566.6
1966	2993116.6
1967	2993716.6
1968	3004636.6
1969	3007106.6
1970	2999926.6
1971	3002146.6
1972	3005086.6
1973	3006496.6
1974	3002996.6
1975	3010276.6
1976	3018236.6
1977	3019786.6
1978	3025366.6
1979	3034156.6
1980	3045286.6
1981	3044576.6
1982	3051706.6
1983	3061356.6
1984	3068996.6
1985	3078036.6
1986	3088186.6
1987	3088936.6
1988	3103236.6
1989	3107176.6
1990	3132916.6
1991	3150398.62
1992	3175829.242
1993	3193891.5439999998
1994	3229653.9620000003
1995	3266784.472
1996	3287117.6380000003
1997	3305573.2
1998	3309197.083
1999	3329976.534
2000	3339826.063
2001	3361963.1780000003
2002	3373251.0979999998
2003	3390441.291
2004	3384053.939
2005	3446531.825
2006	3449227.267
2007	3465610.409
2008	3479022.3449999997
2009	3491761.2240000004
2010	3505786.426
2011	3514583.8079999997
2012	3529813.266
2013	3558354.3540000003
2014	3566587.601
2015	3584392.737
2016	3593613.009
2017	3599340.982
2018	3618614.614
2019	3627121.603
2020	3633870.46
2021	3641770.46