The rate begins with the asset’s depreciable cost, calculated by subtracting estimated salvage value from original cost. That amount is divided by the asset’s expected lifetime production or activity, producing a depreciation cost per unit. Multiplying this rate by the units produced during a reporting period determines the period’s depreciation expense.
Both estimates directly affect the expense assigned to each unit of output. A higher salvage value reduces the depreciable cost, while a larger expected lifetime production spreads that cost across more units. Because these inputs establish the per-unit rate, their estimates influence the amount recognized in each reporting period.
A usage-based pattern is more informative when an asset’s wear depends primarily on how much it operates rather than how much time passes. Machinery, vehicles, and equipment may consume their economic usefulness through production or activity. Linking expense to those measures can provide a more realistic view of asset consumption and improve cost matching.
Production Based Depreciation changes with actual activity, whereas a time-based method allocates depreciation according to the passage of time. Consequently, reporting-period expense can vary with production levels under the units-of-production approach. This distinction makes the production-based method more closely connected to operational performance when usage is the principal driver of wear.
First, identify the asset’s original cost, estimated salvage value, and expected lifetime production or activity. Next, subtract salvage value from cost and divide the result by expected lifetime units to obtain the depreciation rate per unit. Finally, multiply that rate by the units produced during the reporting period and recognize the resulting expense.
The calculation requires a measure of the asset’s actual use or output for the reporting period, such as units produced or another activity measure. It also requires estimates of total lifetime production and salvage value. Together, these inputs connect the recorded expense to operational performance and determine the amount recognized for that period.
The approach is suited to machinery, vehicles, and equipment whose consumption is driven mainly by usage. In finance and accounting, it can help match depreciation expense with the activity generating that consumption. The resulting allocation may present asset use more realistically than an approach that assigns expense solely according to elapsed time.