Year	% of land area
1991	72.70652173913044
1992	72.34782608695653
1993	71.9891304347826
1994	71.6304347826087
1995	71.27173913043478
1996	70.91304347826086
1997	70.55434782608697
1998	70.19565217391303
1999	69.83695652173914
2000	69.47826086956522
2001	69.12173913043478
2002	68.76521739130435
2003	68.40869565217392
2004	68.05217391304348
2005	67.69565217391303
2006	67.3391304347826
2007	66.98260869565217
2008	66.62608695652175
2009	66.2695652173913
2010	65.91304347826087
2011	65.55217391304349
2012	65.19130434782609
2013	64.8304347826087
2014	64.4695652173913
2015	64.1086956521739
2016	52.95652173913044
2017	52.95652173913044
2018	52.95652173913044
2019	52.95652173913044
2020	52.95652173913044
2021	52.95652173913044