Year	% of land area
1993	32.474012474012476
1994	32.45322245322245
1995	32.37006237006237
1996	32.28690228690228
1997	32.224532224532226
1998	32.16216216216216
1999	31.995841995841996
2000	31.76715176715177
2001	29.97920997920998
2002	29.313929313929314
2003	29.370193307004783
2004	28.96049896049896
2005	28.91891891891892
2006	28.64864864864865
2007	28.627858627858625
2008	28.731808731808734
2009	28.73778332293616
2010	28.945124867438814
2011	28.930294460156382
2012	28.953169189818666
2013	28.314756280153052
2014	28.26955074875208
2015	28.077035065097128
2016	28.015806988352743
2017	27.932612312811976
2018	28.036605657237935
2019	28.057404326123127
2020	27.99500831946755
2021	27.579034941763723