Description of the illustration prc_rate_bkdate_discnt_prod.gif

The figure is a timeline with these dates: 1/1, 1/5, 1/10, 1/20, and 1/25. The following appears above the timeline: Discount start date at 1/5 and Discount purchased (Start date backdated to 1/5) and 1/20. The following appears below the timeline: Account creation at 1/1, Usage event X occurs at 1/10, and Usage even X dated 1/10 arrives for rating at 1/25. Below those items, the figure shows the discount validity period starting at 1/5 and continuing forward.