Here is the description:
"Like a fine wine, some monsters improve with age, and it is to them that this second thematic issue of Wisdom from the Wastelands is devoted! An age chart can be a wonderful tool for Game Masters who want to scale monster encounters so that they are commensurate with the powers and artifacts possessed by the player characters. A chart of this sort is made up of three columns, one each for the age of a creature, its hit dice, and notes. Notes include damage, mutations, drawbacks, and anything else that affects the creature in or out of combat."
So good to see Mutant Future getting some love! : )