Year	% of land area
1992	51.209282144406764
1993	51.31855946775515
1994	51.427836791103545
1995	51.537114114451924
1996	51.64639143780031
1997	51.7556687611487
1998	51.864946084497085
1999	51.974223407845464
2000	52.08350073119385
2001	52.294213122920915
2002	52.50492551464798
2003	52.71563790637504
2004	52.92635029810212
2005	53.13706268982917
2006	53.347775081556236
2007	53.5584874732833
2008	53.769199865010364
2009	53.97991225673743
2010	54.19062464846449
2011	54.25271988043775
2012	54.31481511241102
2013	54.37691034438428
2014	54.43900557635754
2015	54.50110080833079
2016	54.563292461471704
2017	54.62548411461263
2018	54.687675767753554
2019	54.74986742089446
2020	54.80941668005785
2021	54.871605335047406