Mareuil operates a data centre that serves its two CGUs, Insurance and Brokerage. A new technology makes some of the servers obsolete: there is an indication of impairment. The company does not plan to dispose of the centre, and usage measured in computing hours provides a reasonable and consistent basis for allocating it. The treasurer proposes estimating a value in use specific to the data centre by attributing to it an estimated share of the two units' cash flows. Which approach should be adopted?