3.1 Fully Depreciated Assets  3.2  Revenue – Route Tariffs  3.3  Classification of Strategic Spares The auditors noted that as in the previous years, management  had not performed a formal review (except for motor vehicles)  for a number of fully depreciated assets in the assets register to  determine whether the assets were in use or needed to be de- recognised, indicating possible non-compliance with International Accounting Standard 16 which requires a review of  useful lives of assets on a regular basis. Fully depreciated assets  as at 31 March 2018 were as follows:  In response management stated that even though the assets  were fully depreciated they were still in use and therefore the  Corporation continued to derive economic benefits from the  assets as well as incurred maintenance costs to ensure they were  operational and as such could not be de-recognised.  The auditors noted that the Corporation had not obtained  approval from the Minister for tariff changes made during the  year under review, indicating non-compliance to Section 18 of  Air Botswana Act which requires approval of tariffs for air transport services by the Minister.  In response management indicated that fares were influenced  by competition, demand and seasonal promotions which require  adjustments to fares to the prevailing conditions which could be  as frequent as daily, weekly, etc. A consultative process would  seriously impact on the decision making and the ability to take  advantage of prevailing conditions at the time.  The auditors noted that contrary to International Accounting  Standard 16 (IAS16) which requires that items such as spare parts,  stand-by equipment and servicing equipment be recognised in  accordance with IAS 16 when they meet the definition of  property, plant and equipment (PPE), management had not  performed a formal evaluation in order to determine whether  any spare parts as such nature classified as inventory were re- classified as PPE. Consequently, there was a total of P1.2 million  98   Motor Vehicles  P3.30 million   Rotables P3.8 million  Furniture and Equipment  P22 million 