Returns the depreciation of an asset for a specified period using the doubledeclining balance method or some other method you specify.
Syntax
DDB(cost,salvage,life,period,factor)
Cost is the initial cost of the asset.
Salvage is the value at the end of the depreciation (sometimes called the salvage value of the asset). This value can be 0.
Life is the number of periods over which the asset is being depreciated (sometimes called the useful life of the asset).
Period is the period for which you want to calculate the depreciation. Period must use the same units as life.
Factor is the rate at which the balance declines. If factor is omitted, it is assumed to be 2 (the doubledeclining balance method).
Important All five arguments must be positive numbers.
Remarks
 The doubledeclining balance method computes depreciation at an accelerated rate. Depreciation is highest in the first period and decreases in successive periods. DDB uses the following formula to calculate depreciation for a period:
Min( (cost  total depreciation from prior periods) * (factor/life), (cost  salvage  total depreciation from prior periods) )
 Change factor if you do not want to use the doubledeclining balance method.
 Use the VDB function if you want to switch to the straightline depreciation method when depreciation is greater than the declining balance calculation.
Example
The example may be easier to understand if you copy it to a blank worksheet.
How to copy an example
 Create a blank workbook or worksheet.
 Select the example in the Help topic.
Note Do not select the row or column headers.
Selecting an example from Help
 Press CTRL+C.
 In the worksheet, select cell A1, and press CTRL+V.
 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.

A 
B 
Data 
Description 
2400 
Initial cost 
300 
Salvage value 
10 
Lifetime in years 
Formula 
Description (Result) 
=DDB(A2,A3,A4*365,1) 
First day's depreciation. Microsoft Excel automatically assumes that factor is 2. (1.32) 
=DDB(A2,A3,A4*12,1,2) 
First month's depreciation (40.00) 
=DDB(A2,A3,A4,1,2) 
First year's depreciation (480.00) 
=DDB(A2,A3,A4,2,1.5) 
Second year's depreciation using a factor of 1.5 instead of the doubledeclining balance method (306.00) 
=DDB(A2,A3,A4,10) 
Tenth year's depreciation. Microsoft Excel automatically assumes that factor is 2 (22.12) 

Note The results are rounded to two decimal places.