Year	sq. km
1990	31267
1991	31069.73
1992	30872.46
1993	30675.19
1994	30477.92
1995	30280.65
1996	30083.38
1997	29886.11
1998	29688.84
1999	29491.57
2000	29294.3
2001	29097.03
2002	28899.76
2003	28702.49
2004	28505.22
2005	28307.95
2006	28110.68
2007	27913.41
2008	27716.14
2009	27518.87
2010	27321.6
2011	27124.34
2012	26927.08
2013	26729.82
2014	26532.56
2015	26335.3
2016	26138
2017	25940.7
2018	25743.4
2019	25546.1
2020	25348.8
2021	25151.5