I cannot find an answer to this anywhere, so hoping you can help! I have a list of ref IDs in Column A which may or may not be unique (eg. 1, 1, 1, 2, 3, 3, 4, 4 ,4 ,4...etc). I need to be able to find the last instance of EACH of these ref IDs in Column A and sum the associated cell values in a column further along in the Spreadsheet. Many thanks in advance.