RPC’s revenues are generated principally from providing services and the related equipment. Revenues are recognized when the services are rendered and collectability is reasonably assured. Revenues from services and equipment are based on fixed or determinable priced purchase orders or contracts with the customer and do not include the right of return. Rates for services and equipment are priced on a per day, per unit of measure, per man hour or similar basis. Sales tax charged to customers is presented on a net basis within the consolidated statement of operations and excluded from revenues.