# DDB

| **Name**    | ***DDB***                                                                                                             |
| ----------- | --------------------------------------------------------------------------------------------------------------------- |
| Syntax      | DDB (Real Cost, Real Salvage, Real Life, Real Period)                                                                 |
| Purpose     | To return the double-declining balance of an asset.                                                                   |
| Description | Returns the depreciation of an asset for a specific time period using the double-declining balance method.            |
| Return Type | Double                                                                                                                |
| Parameters  | <p>Cost \[System.Double]</p><p>Salvage \[System.Double]</p><p>Life \[System.Double]</p><p>Period \[System.Double]</p> |

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/0%20\(192\).png)

### **Example**

To calculate the depreciation value for the aforementioned example, we will be passing the required parameters to the function transformation object using a *Variables* object.

Where,

*Cost* = 10000

*Salvage* = 3000

*Life* = 10

*Period* = 6

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/1%20\(192\).png)

Right-click on the function transformation object and select *Preview Output.* You can see that Astera Data Stack has returned depreciation value using the double-declining method.

![](https://github.com/astera-software/Astera_Data_Stack_v9/blob/main/.gitbook/assets/2%20\(192\).png)


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