Are you sure the depreciation method is setup correctly?
see: Define Depreciation Methods (page 43)
Methods identify how annual depreciation is calculated for the asset.
•There are several methods for calculating depreciation
•Assets can have depreciation calculated one way for tax reporting purposes
•Assets can have depreciation calculated another way for financial purposes
•Depreciation methods for tax purposes are usuallybased on the type of asset and the taxlaws in effect when the asset was placed in service
•Depreciation methods for financial or management purposes usually follow generallyaccepted accounting practices and policies