All sales come in waves/cycles.  The east coast sees waves in increments of 6-8 weeks, while the west coast sees wave increments in 8-12 weeks. Most sales also follow season patterns. For example in September when the kids are going back to school items like pudding packs, fruit snacks and juice are on sale.

When purchasing items, pay attention to expiration dates and keep that in mind when you're considering the shelf life items.