Year	% of land area
1992	0.8722305448237799
1993	0.7097372000867457
1994	0.7245733889332505
1995	0.7246091054281601
1996	0.7197294605972768
1997	0.7098666535209879
1998	0.6113524200188336
1999	0.6113343357901744
2000	0.611295156964821
2001	0.6063773145865788
2002	0.601491897115304
2003	0.5916401250332798
2004	0.5867416118137219
2005	0.5817593784048947
2006	0.5963411268383078
2007	0.5963499440613895
2008	0.5963470049580586
2009	0.5914301767390512
2010	0.60127549260234
2011	0.6012517865063328
2012	0.5914272618396346
2013	0.5859798529382775
2014	0.580372758938381
2015	0.5576959079309087
2016	0.5483082743807516
2017	0.5616095532740852
2018	0.5468519065917825
2019	0.5271844899366886
2020	0.4926593753079121
2021	0.46809559004680956