Accounting How to Calculate Depreciation Expense

What is Depreciation?

Depreciation is the systematic allocation of the cost of a tangible asset over its useful life. It reflects the wear and tear, obsolescence, or other factors that reduce the value of the asset. Depreciation expense is reported on the income statement and reduces taxable income, while the accumulated depreciation is recorded as a contra-asset on the balance sheet.

The primary purposes of depreciation are:

• To match the cost of the asset with the revenue it generates
• To provide a more accurate measure of a company's financial position
• To comply with accounting standards and tax regulations

Methods of Depreciation

There are several methods for calculating depreciation expense, each with its own advantages and disadvantages. The choice of method depends on the nature of the asset, its useful life, and the company's financial reporting requirements.

The most common methods include:

• Straight-line method
• Double declining balance method
• Sum of the years' digits method
• Units of production method
• Activity-based depreciation

For most assets, the straight-line method is the simplest and most commonly used approach. However, for assets with a longer useful life, the double declining balance or sum of the years' digits methods may be more appropriate.

Straight-Line Method

The straight-line method allocates the cost of the asset evenly over its useful life. The annual depreciation expense is calculated by dividing the asset's cost by its useful life in years.

Example: A company purchases a machine for $10,000 with a salvage value of $1,000 and a useful life of 5 years. The annual depreciation expense would be:

The straight-line method is simple and easy to understand, but it may not reflect the actual wear and tear of the asset. It also does not account for changes in the asset's value over time.

Double Declining Balance Method

The double declining balance method accelerates depreciation in the early years of the asset's life. The annual depreciation expense is calculated by multiplying the asset's book value at the beginning of the year by a rate that is twice the asset's useful life.

Example: A company purchases a machine for $10,000 with a useful life of 5 years. The annual depreciation expense for the first year would be:

The double declining balance method provides for faster write-offs of assets, which can be beneficial for tax planning. However, it may not be suitable for assets with a long useful life or those that retain significant value over time.

Sum of the Years' Digits Method

The sum of the years' digits method allocates a larger portion of the depreciation expense in the early years of the asset's life. The annual depreciation expense is calculated by multiplying the asset's cost by the ratio of the year's digit to the sum of the digits of the useful life.

Example: A company purchases a machine for $10,000 with a salvage value of $1,000 and a useful life of 5 years. The sum of the years' digits is 1 + 2 + 3 + 4 + 5 = 15. The annual depreciation expense for the first year would be:

The sum of the years' digits method provides for a more accelerated depreciation in the early years, which can be beneficial for tax planning. However, it may not be suitable for assets with a long useful life or those that retain significant value over time.

Calculator Example

Use the calculator on the right to calculate depreciation expense for your asset. Enter the asset cost, salvage value, useful life, and select the depreciation method. The calculator will display the annual depreciation expense and a chart showing the depreciation schedule.

For example, if you enter an asset cost of $20,000, salvage value of $2,000, useful life of 10 years, and select the straight-line method, the calculator will show an annual depreciation expense of $1,800.