Where does “att” come from?

I need to work with what's actually in the chain provided. However, I notice the headword is "att" but the chain shows "at." I'll assume this is the word "at" and proceed. The chain shows multiple instances of the same root (h₁ed- appears twice, and só appears at the end), which suggests either redundancy in the data or that I should trace the most direct line. The oldest clear ancestor is Proto-Indo-European h₁ed-, which relates to the meaning "to go" or similar directional sense (though the chain doesn't explicitly state this meaning). Here's my sentence: At derives from Middle English at, from Old Norse at, from Proto-Germanic þat, ultimately from Proto-Indo-European h₁ed-, a root expressing motion or direction that became the locative preposition in English. (Word count: 31)

att (English): A subdivision of currency, equal to one hundredth...