Year	sq. km
1990	6507239.3
1991	6507854.34
1992	6508469.38
1993	6509084.42
1994	6509699.46
1995	6510314.5
1996	6510929.54
1997	6511544.58
1998	6512159.62
1999	6512774.66
2000	6513389.7
2001	6518093.9399999995
2002	6522798.18
2003	6527502.42
2004	6532206.66
2005	6536910.9
2006	6541615.140000001
2007	6546319.38
2008	6551023.62
2009	6555727.859999999
2010	6560432.1
2011	6562769.1
2012	6565106.1
2013	6567443.1
2014	6569780.1
2015	6572117.1
2016	6571720.4
2017	6568350.5
2018	6567980.7
2019	6567610.8
2020	6567241
2021	6566871.132999999