Fixed Asset Depreciation

We currently have a discoverer report set up for fixed asset register.

The report simply shows the asset, cost, nbv and depreciation figures. Within the report we have a calculation for the depreciation to pick up the max figure - however when assets are corrected and so is their depreciation the report gives incorrect figures as it is picking up the max depreciation figure from the line level.

We're trying to devise the report to pick up accumulated depreciation to date as this should include all corrections to the depreciation amounts.

Can anyone help?