Year	sq. km
1990	4611.4
1991	4623.54
1992	4635.68
1993	4647.82
1994	4659.96
1995	4672.1
1996	4684.24
1997	4696.38
1998	4708.52
1999	4720.66
2000	4732.8
2001	4744.95
2002	4757.1
2003	4769.25
2004	4781.4
2005	4793.55
2006	4805.7
2007	4817.85
2008	4830
2009	4842.15
2010	4854.3
2011	4866.44
2012	4878.58
2013	4890.72
2014	4902.86
2015	4915
2016	4927.2
2017	4939.3
2018	4951.4
2019	4963.5
2020	4975.6
2021	4987.7