NET SALES

The following table shows disaggregated net sales from contracts with customers by major source:



	Three Months Ended March 31, 2018
			Europe, Middle East
(In millions)	Americas		and Africa		Asia Pacific		Total
Tire unit sales	$	1,506	$	1,209	$	518	$	3,233
Other tire and related sales	135		105		30		270
Retail services and service related sales	137		15		22		174
Chemical	148		—		—		148
Other	3		1		1		5

Net Sales by reportable segment	$	1,929	$	1,330	$	571	$	3,830

Tire unit sales consist of consumer, commercial, farm and off-the-road tire sales, including the sale of new Company-branded tires through Company-owned retail channels. Other tire and related sales consist of aviation, race, motorcycle and all-terrain vehicle tire sales, retread sales and other tire related sales. Sales of tires in this category are not included in reported tire unit information. Retail services and service related sales consist of automotive services performed for customers through our Company-owned retail channels, and includes service related products. Chemical sales relate to the sale of synthetic rubber and other chemicals to third-parties, and excludes intercompany sales. Other sales include items such as franchise fees and ancillary tire parts such as tire rims, tire valves and valve stems.

Sales are recognized when obligations under the terms of a contract are satisfied and control is transferred. This generally occurs with shipment or delivery, depending on the terms of the underlying contract, or when services have been rendered. Sales are measured as the amount of consideration we expect to receive in exchange for transferring goods or providing services. The amount of consideration we receive and sales we recognize can vary due to changes in sales incentives, rebates, rights of return or other items we offer our customers, for which we estimate the expected amounts based on an analysis of historical experience, or as the most likely amount in a range of possible outcomes. Payment terms with customers vary by region and customer, but are generally 30-90 days or at the point of sale for our consumer retail locations. Net sales exclude sales, value added and other taxes. Costs to obtain contracts are generally expensed as incurred due to the short term nature of individual contracts. Incidental items that are immaterial in the context of the contract are recognized as expense as incurred. We have elected to recognize the costs incurred for transportation of products to customers as a component of CGS.

When we receive consideration from a customer prior to transferring goods or services under the terms of a sales contract, we record deferred revenue, which represents a contract liability. Deferred revenue included in Other Current Liabilities and Other Long Term Liabilities in the Consolidated Balance Sheet totaled $50 million and $62 million, respectively, at March 31, 2018. We recognize deferred revenue after we have transferred control of the goods or services to the customer and all revenue recognition criteria are met.

The following table presents the balance of deferred revenue related to contracts with customers, and changes during the three months ended March 31, 2018:



(In millions)
Balance at December 31, 2017	$	121
Revenue deferred during period	31
Revenue recognized during period	(40		)
Impact of foreign currency translation	—
Balance at March 31, 2018	$	112