6.21 Economic disappearance of non-financial non-produced assets (K.6) includes:
(1) other reductions in the level of exploitable subsoil resources (reassessments of exploitability due to changes in technology or relative prices);
(2) quality change in non-produced assets due to changes in economic uses;
(3) degradation of non-produced assets due to economic activity. Covered is degradation of land, water resources and in principle of other natural assets;
(4) write-off of purchased goodwill, cancellation of transferable contracts and exhaustion of patent protection.