Help in Developing a Multi-Level Gross Margin Chart
 

Gross Margin (GM) is a component of two primary variables, Revenue and Cost
(COGS). I wish to plot a Line chart with months at the bottom (X-axis) and GM
$'s or % on the Y-axis and at the same time reflect changes in both Revenue
and COGS per the value of GM per that month. This way one I can plot another
Line chart with historical GM (Rev & COGS) and show both components within
one data point. Is this possible?