Our retail stores generally record revenue at the point of sale. Sales from our online and mobile applications include shipping revenue and are recorded upon delivery to the guest. Total revenues do not include sales tax because we are a pass-through conduit for collecting and remitting sales taxes. Generally, guests may return merchandise within 90 days of purchase. Revenues are recognized net of expected returns, which we estimate using historical return patterns as a percentage of sales. Commissions earned on sales generated by leased departments are included within sales and were $29 million, $25 million and $22 million in 2013, 2012 and 2011, respectively.
Revenue from gift card sales is recognized upon gift card redemption. Our gift cards do not expire. Based on historical redemption rates, a small and relatively stable percentage of gift cards will never be redeemed, referred to as "breakage." Estimated breakage revenue is recognized over time in proportion to actual gift card redemptions and was not material in any period presented.