When you did "Add new series" and it does not show up, is it still
visible in the Select data box?
Is it just not showing up because the % firgures are tiny compared to
the actual figures (eg % is <100 in your case, and you may have money
values in millions or billions)?
Sounds like it could be there but just too small to see.
Go to the Chart Tools|Layout ribbon, at the left hand end in the drop
down list see if your new series is there. If it is, choose it in the
list. Beneath that list is a button to format the selection, click that
and in the format series dialogue box click to plot this on a secondary
axis. (this is to deal with the scaling problem, not the chart type).
Close the format dialogue.
Now go to the Design ribbon and click on "Change chart type" at the left
while this series is still selected. Choose a line chart or whatever is
appropriate for you.
Hope this helps
Adam