Same item, different DPS in game and Auction House

So I found this item, and decided to sell it in the Auction House. Why would it show a different DPS in said Auction House when compared to in game?

(599.9 in game, 600.1 in Auction House)

Cropped screenshot showing DPS of 599.9 on a Rare Staff (2-Hand) with 450-750 Damage, 1.00 Attacks per Second, +63-171 Holy Damage, +16% Damage, +104 Dexterity, +215 Vitality, 2.9% of Damage Dealt is Converted to LifeCropped screenshot showing DPS of 600.1 on the same item


I know that i have on several occasions seen similar changes in the DPS on weapons and they have been due to skills, followers, or gems when the item is equipped. If this is occurring on an item in your inventory, then it is most likely a bug and i would report it to Blizzard.