I have a large excel spreadsheet that I would like to condense into two columns single spaced. I would like to pull some letters from a long file name and have them shown on a chart underneath so I wrote (=MID(D3,38,6)) the problem is that I want to reference every fourth line - so my next formula would be (=MID(D7,38,6)). I repeat the same formula three more times using D11, D15, D19 and now I just want to drag the properties down, but excel won't recognize that I want to reference every 4th row. Is there a way to make excel know I want to reference every 4th row?