Add target line to graph

Hi there,

I wonder if you could halp me, I have a bar graph that shows how many of something per group
i.e.
x-axis - group
y-asis - number of items

That's fine, but what I now need to show is a line graph superimposed over the top with a second x axis for date, that shows when all the items will close i.e. each group has 8 or less items, there are 7 groups, so items combined comes to a total of about 50. I need to show a second x axis line that shows dates up to the end of the year, and the line I am trying to produce will go diagonally from 50 at the earliest date down to 6 by 24th December.

How can I do that?

Hi,

Apologies to the OP for piggy backing off of his topic but I am looking for a similar solution as well. I am using excel 2013 pivot charts and have added timelines and slicers. I want know if there is a way to have a common target line for a column chart while you slice and dice between the data

thanks