Formula to average of two cells in a column if a cell is same between rows
I am trying to write a script or formula that will average two cells, at times t and t-1 stored on different rows, if the item ID matches. I think the steps would be as followsIf Item row 2 = Item row 1(value row 2 + value row 1)/2store result in average row 2else leave blank Please see the table below for an example. I put the expected answers in the Average column. I am fine with a scripting ans...