Auto Sum Cells Base on Certain Criteria

Looking for a method to auto sum cells based on a certain criteria, i.e. cells should auto sum to top of the branch i.e. Amt under Head 1.2.1 & 1.2.2 should be automatically summed as Amt under head 1.2. Similarly Amt under Head 1.1, 1.2 & 1.3 should be automatically summed as Amt under head 1

Cross-posted here: https://forums.excelguru.ca/threads/...43/#post-48278

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