I hope this is a fairly simple problem. I have a pretty simple chart to begin with.

I want to display the 2013 sales of several locations in one column - this information will remain static. Then in a second column display YTD sales for the same locations which will be increased monthly.

What I'm trying to do is display the new data I add each month in the same column but have it broken up into different colors.

For example:

January 2014 sales are 100 so the column will show 100 under YTD sales and this will be in black. Then February 2014 sales are 50 so I would like the column to show 150 total but break it up into say black for the 100 and red for the 50 to show the difference. I'd like to be able to do this for the full year displaying a different color for each month - 12 in total.

Is this possible and what would be the simplest way to go about implementing it?

Thanks,