5.21 GCHQ used the component costs of the Public Sector Comparator as benchmarks for the final bid from IAS. The estimated building and refurbishment costs, measured by floor area, were similar. The main areas in which the bid costs were lower were service and lifecycle costs. Capita advised GCHQ that an appropriate industry standard for annual lifecycle costs was seven per cent of the value of capital stock. The total estimated value of the capital stock of building plus refurbishment was some £350 million (undiscounted), so GCHQ estimated lifecycle costs of seven per cent of that, some £24.6 million a year.