Year	sq. km
1992	18570
1993	18605
1994	18640
1995	18675
1996	18710
1997	18745
1998	18780
1999	18815
2000	18850
2001	18885
2002	18920
2003	18955
2004	18990
2005	19025
2006	19060
2007	19095
2008	19130
2009	19165
2010	19200
2011	19204
2012	19208
2013	19212
2014	19216
2015	19220
2016	19241.202
2017	19316.084
2018	19341.1
2019	19366.1
2020	19391.1
2021	19416.1