Accelerated depreciation means claiming more depreciation in the early years of an asset’s life and less in later years. The total deductions over the full life of the asset may be the same as under straight-line depreciation, but the timing changes and that timing can materially affect tax payments and investment incentives.
Why Timing Matters
Suppose a firm buys an asset costing K. If tax deductions arrive earlier, the present value of the tax shield rises:
\[ PV = \sum_{t=1}^{T} \frac{\tau d_t}{(1+r)^t} \]
where d_t is the depreciation deduction in year t, \\tau is the tax rate, and r is the discount rate.
Accelerated depreciation shifts more of d_t into earlier periods, which lowers taxes sooner and improves near-term cash flow.
Economic Effect
Because earlier deductions reduce the user cost of capital, accelerated depreciation can encourage firms to invest in equipment, software, or structures. The policy does not create output directly; it changes the after-tax return to investment.
This is why governments often use it as a temporary stimulus tool. It is especially attractive when policymakers want firms to bring forward planned capital spending.
Accounting vs Tax Use
In practice, accelerated depreciation matters most in tax policy. Financial reporting may use a different depreciation method than the tax code. So a firm can report one expense pattern to investors and claim another for tax purposes.