An appreciation of our critical accounting policies is necessary to understand our financial results. These policies may require management to make difficult and subjective judgments regarding uncertainties, and as a result, such estimates may significantly impact our financial results. The precision of these estimates and the likelihood of future changes depend on a number of underlying variables and a range of possible outcomes. Other than our accounting for pension plans, our critical accounting policies do not involve the choice between alternative methods of accounting. We applied our critical accounting policies and estimation methods consistently in all material respects, and for all periods presented, and have discussed these policies with our Audit Committee.
Our products are sold for cash or on credit terms. Our credit terms, which are established in accordance with local and industry practices, typically require payment within 30 days of delivery in the U.S., and generally within 30 to 90 days internationally, and may allow discounts for early payment. We recognize revenue upon shipment or delivery to our customers based on written sales terms that do not allow for a right of return. However, our policy for DSD and chilled products is to remove and replace damaged and out-of-date products from store shelves to ensure that consumers receive the product quality and freshness they expect. Similarly, our policy for certain warehouse-distributed products is to replace damaged and out-of-date products. Based on our experience with this practice, we have reserved for anticipated damaged and out-of-date products. Our bottlers have a similar replacement policy and are responsible for the products they distribute.
Our policy is to provide customers with product when needed. In fact, our commitment to freshness and product dating serves to regulate the quantity of product shipped or delivered. In addition, DSD products are placed on the shelf by our employees with customer shelf space limiting the quantity of product. For product delivered through our other distribution networks, we monitor customer inventory levels.
As discussed in “Our Customers,” we offer sales incentives and discounts through various programs to customers and consumers. Sales incentives and discounts are accounted for as a reduction of revenue and totaled $12.5 billion in 2008, $11.3 billion in 2007 and $10.1 billion in 2006. Sales incentives include payments to customers for performing merchandising activities on our behalf, such as payments for in-store displays, payments to gain distribution of new products, payments for shelf space and discounts to promote lower retail prices. A number of our sales incentives, such as bottler funding and customer volume rebates, are based on annual targets, and accruals are established during the year for the expected payout. These accruals are based on contract terms and our historical experience with similar programs and require management judgment with respect to estimating customer participation and performance levels. Differences between estimated expense and actual incentive costs are normally insignificant and are recognized in earnings in the period such differences are determined. The terms of most of our incentive arrangements do not exceed a year, and therefore do not require highly uncertain long-term estimates. For interim reporting, we estimate total annual sales incentives for most of our programs and record a pro rata share in proportion to revenue. Certain arrangements, such as fountain pouring rights, may extend beyond one year. The costs incurred to obtain these incentive arrangements are recognized over the shorter of the economic or contractual life, as a reduction of revenue, and the remaining balances of $333 million at year-end 2008 and $314 million at year-end 2007 are included in current assets and other assets on our balance sheet.
We estimate and reserve for our bad debt exposure based on our experience with past due accounts and collectibility, the aging of accounts receivable and our analysis of customer data. Bad debt expense is classified within selling, general and administrative expenses in our income statement.