Year	% of land area
1992	38.824607742647636
1993	39.07448297616466
1994	39.32018257277773
1995	39.56513595047026
1996	39.81089847870882
1997	40.05373296196791
1998	40.301929211306074
1999	40.54379175191658
2000	40.784232528790035
2001	40.96103409516673
2002	41.14007365810609
2003	41.31669509826156
2004	41.49495845968001
2005	41.66728293719464
2006	41.82864803059575
2007	42.005214365626586
2008	42.18095435234744
2009	42.35773639957023
2010	42.53284837014913
2011	42.53462126065743
2012	42.54037723202184
2013	42.541940189642595
2014	42.531765308686374
2015	42.53416626432421
2016	42.9069698701401
2017	42.9784026641969
2018	43.05153217065721
2019	43.126154755746064
2020	43.1944033894965
2021	43.27223454052722