I am experiencing some difficulty in creating a line graph that shows the differences between two values on a specific date. For example, the picture below is a line graph that shows the values of each Unit Type on each specific date. What I would like to do with this is create a different line graph that shows [Unit Value (Unit Type A) - Unit Value (Unit Type B)] on each specific date. I have been working with creating a new calculated field to come up with these values but am still not figuring it out. This example workbook is attached to the discussion. The format or structure of this data is not allowed to be altered outside of Tableau. This workbook is an example of a much larger data set that's format cannot be altered.