Year	sq. km
1990	1338822
1991	1336753.9
1992	1334685.8
1993	1332617.7
1994	1330549.6
1995	1328481.5
1996	1326413.4
1997	1324345.3
1998	1322277.2
1999	1320209.1
2000	1318141
2001	1315873
2002	1313605
2003	1311337
2004	1309069
2005	1306801
2006	1304533
2007	1302265
2008	1299997
2009	1297729
2010	1295461
2011	1302557.8
2012	1309654.6
2013	1316751.4
2014	1323848.2
2015	1330945
2016	1340372
2017	1340174
2018	1340051
2019	1340051
2020	1340051
2021	1340051