 Amazon stock down slightly ahead of next week's prime days. Walmart trading lower as the retailer launches its own savings event today. Chipotle down 5%. Chipotle blasted on social media after skimpy burrito bowls are going viral. Oil futures sliding to start the week. West Texas Intermediate crude down more than a percent. The benchmark settling at $82 a barrel. Oil traders tracking tropical storm barrels path. The storm weakening after making landfall as a Category 1 hurricane earlier today.