[Home](./index.md) > [@firebase/firestore](./firestore.md) > [/](./firestore_.md) > [DocumentChange](./firestore_.documentchange.md) > [oldIndex](./firestore_.documentchange.oldindex.md) ## DocumentChange.oldIndex property The index of the changed document in the result set immediately prior to this `DocumentChange` (i.e. supposing that all prior `DocumentChange` objects have been applied). Is `-1` for 'added' events. Signature: ```typescript readonly oldIndex: number; ```