The SNA defines consumption of fixed capital as a cost of production in terms of the decline during the accounting period in the current value of the stock of fixed assets owned and used by a producer as a result of physical deterioration, normal obsolescence or normal accidental damage. It excludes damage from war or natural disasters accounted for as other volume changes in asset accounts. The SEEA extends the concept of capital consumption to natural capital in terms of depletion and degradation costs, i.e. imputed environmental cost.