Year	sq. km
1990	3453.3
1991	3467.47
1992	3481.64
1993	3495.81
1994	3509.98
1995	3524.15
1996	3538.32
1997	3552.49
1998	3566.66
1999	3580.83
2000	3595
2001	3608.98
2002	3622.96
2003	3636.94
2004	3650.92
2005	3664.9
2006	3678.88
2007	3692.86
2008	3706.84
2009	3720.82
2010	3734.8
2011	3717.5
2012	3700.2
2013	3682.9
2014	3665.6
2015	3648.3
2016	3657.6
2017	3667
2018	3676.3
2019	3685.7
2020	3695
2021	3704.367