Year	sq. km
1990	3.5
1991	3.5
1992	3.5
1993	3.5
1994	3.5
1995	3.5
1996	3.5
1997	3.5
1998	3.5
1999	3.5
2000	3.5
2001	3.5
2002	3.5
2003	3.5
2004	3.5
2005	3.5
2006	3.5
2007	3.5
2008	3.5
2009	3.5
2010	3.5
2011	3.5
2012	3.5
2013	3.5
2014	3.5
2015	3.5
2016	3.8
2017	4.2
2018	4.6
2019	4.6
2020	4.6
2021	4.6