Tribunal held that calculation for depreciation on Securities Worked out  in terms of  RBI  guidelines and only incremental depreciation debited in profit and loss account.  Accumulated Depreciation in respect of  any security sold during year automatically reduced at end of  relevant year.  Profit on sale of  securities correctly reflected in profit and loss account. Depreciation on valuation of  securities allowable as business loss. Deletion of addition by CIT(A) is held to be justified. (AY. 2013-14)