DB function
This article describes the formula syntax and usage of the DBfunction in Microsoft Excel.
Description
Returns the depreciation of an asset for a specified period using the fixeddeclining balance method.
Syntax
DB(cost, salvage, life, period, [month])
The DB function syntax has the following arguments:

Cost Required. The initial cost of the asset.

Salvage Required. The value at the end of the depreciation (sometimes called the salvage value of the asset).

Life Required. The number of periods over which the asset is being depreciated (sometimes called the useful life of the asset).

Period Required. The period for which you want to calculate the depreciation. Period must use the same units as life.

Month Optional. The number of months in the first year. If month is omitted, it is assumed to be 12.
Remarks

The fixeddeclining balance method computes depreciation at a fixed rate. DB uses the following formulas to calculate depreciation for a period:
(cost  total depreciation from prior periods) * rate
where:
rate = 1  ((salvage / cost) ^ (1 / life)), rounded to three decimal places

Depreciation for the first and last periods is a special case. For the first period, DB uses this formula:
cost * rate * month / 12

For the last period, DB uses this formula:
((cost  total depreciation from prior periods) * rate * (12  month)) / 12
Example
The example may be easier to understand if you copy it to a blank worksheet.
How do I copy an example?

Select the example in this article.
Important Do not select the row or column headers.
Selecting an example from Help

Press CTRL+C.

In Excel, create a blank workbook or worksheet.

In the worksheet, select cell A1, and press CTRL+V.
Important For the example to work properly, you must paste it into cell A1 of the worksheet.

To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Formulas tab, in the Formula Auditing group, click the Show Formulas button.
After you copy the example to a blank worksheet, you can adapt it to suit your needs.

