depletion

An accounting method used to allocate the cost of extracting natural resources over time.

Depletion is an accrual accounting method used to systematically allocate the cost of extracting natural resources from the earth. Unlike depreciation, which spreads the cost of tangible physical assets like machinery over their useful lives, or amortization, which does the same for intangible assets, depletion is specifically tied to the physical consumption of finite natural reserves such as oil, timber, minerals, or natural gas. There are two primary methods of calculating depletion: cost depletion and percentage depletion. Cost depletion is based on the actual volume of resources extracted relative to the estimated total reserves available, adjusting the asset's carrying value on the balance sheet as resources are sold. Percentage depletion, which is primarily used for tax purposes rather than GAAP financial reporting, applies a fixed percentage to the gross income generated from the resource extraction. Investors analyze depletion because it directly impacts both net income and the book value of resource-heavy companies. Because depletion is a non-cash expense, a high depletion charge will depress reported earnings without reducing the company's actual cash flow. To evaluate the sustainability of a resource company, investors often compare capital expenditures to depletion to determine if the business is investing enough capital to replace the reserves it is actively depleting.

Company A acquires a mining property for $10,000,000 with an estimated 2,000,000 tons of coal reserves and no salvage value. The depletion rate per unit is $5.00 per ton ($10,000,000 / 2,000,000 tons). If the company extracts and sells 150,000 tons of coal in its first year, the depletion expense recorded is $750,000 ($5.00 150,000).