Work in progress credit (contract liabilities) relates to the Group’s obligation to perform work for projects for which consideration has already been received from the customer, or is due from the customer. The contract liability is determined as the difference between the invoiced instalments and the cumulative revenue recognised in proportion to the progress in satisfying the performance obligations (see accounting policy 5). When a loss is expected at project level, the full expected loss is recognised immediately as an expense in the statement of profit or loss. The related amount is recognised under ‘Provisions’ in the statement of financial position (see accounting policy 21a).