EARLIER () may be one of the more confusing functions to understand. Many of us deal with it by using an index to track on which row we are located and to which we can refer when writing our DAX formulas. Or we use a date column because of its sequential order. What if we have a date column that has duplicate dates that lead the engine to return an error? What if there is a way to have an Index column to be more than just a signpost? This is what I discovered when answering a question on this forum.