| 3.10 | Revenue |
| (a) | Sales of goods |
Revenue from the sale of goods, in the ordinary course of business, is measured at the fair value of the consideration received or receivable, net of returns, trade discounts and volume rebates. Revenue is recognized when significant risks and rewards of ownership have been transferred to the customer, recovery of the consideration is probable, the associated costs and possible return of goods can be estimated reliably, there is no continuing management involvement with the goods, and the amount of revenue can be measured reliably. If it is probable that discounts will be granted and the amount can be measured reliably, then the discount is recognized as a reduction of revenue as the sales are recognized.
| (b) | Services rendered |
Revenues from services are recognized when the amount of revenue can be measured reliably, when it is probable that the economic benefits associated with the transaction will flow to the Company, when the stage of completion of the transaction at the end of the reporting period can be measured reliably, as well as when its amount and related costs can be measured reliably. Service prices are established based on service orders or contracts. Services for which payment is made in advance are recorded as deferred revenue in other liabilities and recognized in revenue when the services are rendered.
The Company revenue recognizes revenue as follows:
| • | Billed revenue |
Revenue from gas distribution services is recognized when its amount can be reliably measured, and is recognized in profit or loss when the volumes are delivered to customers.
| • | Unbilled revenue |
Unbilled gas refers to the portion of gas supplied for which metering and billing to customers have not yet occurred. This amount is estimated based on the period between measurement and the last day of the month.
The actual volume billed may be different from estimates. The Company believes that, based on its historical experience with similar operation, the unbilled estimated amount will not significantly differ from actual amounts.
| • | Concession construction revenue |
The construction of the infrastructure necessary for gas distribution is considered a construction service rendered to the Conceding Authority, and the related income is recognized in profit or loss at finishing stage of the work.
Construction costs are recognized by reference to the stage of completion of the construction activity at the end of the reporting period, and are included in cost of sales.
| (c) | Deferred revenue |
The Company´s deferred revenue consists in advances received from clients seeking investment in fixed assets in return for a rail service contract requiring future performance of services by the Company.