obligation based on the stand-alone selling prices. Where these are not directly observable, they are estimated based on expected cost plus margin. If contracts include sale of goods as a separate performance obligation, revenue from this sale is recognised at a point in time when the goods are delivered, the legal title has passed and the customer has accepted the goods. When the consideration of a construction contract cannot be estimated reliably, contract revenue is recognised only to the extent of contract costs incurred that are likely to be recoverable. An expected loss on a contract is recognised immediately in the statement of profit or loss. Estimates of revenues, costs or extent of progress toward completion are revised if circumstances change. Any resulting increases or decreases in estimated revenuesor costs are reflected in the statement of profit or loss in the period in which the circumstances that give rise to the revision become known by management. The amounts will be billed within 60 to 180 days from satisfying the performance obligations and payment is expected within 30 days from billing date. Advances received are included in contract liabilities. (d) Customers’ contributions Contributions received from customers in the form of cash and/or PPE in respect of capital contributions for the construction of assets, used to connect the customers to a network or to provide them with the service, is included in the revenue. The customers’ contributions are viewed as indirectly related to the promise of providing supply of electricity to the customers. Supply of electricity and customers’ contributions are not distinct because the customers cannot benefit from these two services on their own. The connection infrastructures are to fulfil the obligation to supply electricity to the customers. Both the supply of electricity and customers’ contributions are substantially the same, and have the same pattern of transfer to the customers. Therefore, connection and the supply of electricity are one