Year	% of land area
1992	37.73509896174479
1993	37.764934790869425
1994	37.80354474052262
1995	37.839619525210225
1996	37.87200944831043
1997	37.80763831506856
1998	37.836074661021364
1999	37.858487933395494
2000	37.86631631092769
2001	37.914693482556906
2002	37.961981818008034
2003	38.00759054205096
2004	38.05392683668653
2005	38.10035097542781
2006	38.13472460203312
2007	38.18275014637769
2008	38.23258649951402
2009	38.2791557798207
2010	38.32523626487502
2011	38.346429868296035
2012	38.367194590069076
2013	38.38635206083411
2014	38.40787449004237
2015	38.42284183290779
2016	38.444426827323134
2017	38.46905238251064
2018	38.485077510436696
2019	38.50230024606494
2020	38.52496554063617
2021	38.54166326813281