Function: DDB()
Purpose: The DDB() function returns a double value containing the periodic depreciation of an asset using the double-declining balance method (or other method, as specified).
Usage: DDB(cost, salvage, life, period, [factor])
The cost is a double specifying the initial asset value.
The salvage is a double specifying the salvage value of the asset at the end of its life.
The life is a double specifying the useful life of the asset.
The period is a double specifying the length of time in each depreciation period. It must be in the same unit as life
The factor is a variant specifying the depreciation factor. The default value of 2 specifies the double-declining balance method.
Returns: Double containing the depreciation value.
Examples and Special Cases
DDB(100000,10000,20,1) returns 10,000
DDB(100000,10000,20,1,3) returns 15,000
DDB(100000,10000,10,1) returns 20,000
DDB(100000,10000,10,1,3) returns 30,000
