Please Help: color coding a timeline graph
 

I have a table of dates and color values that i'd like to turn into a
graph. It spans several years, and has data-points at irregular
intervals. I'd like to make a graph that is a single horizontal bar
that changes back and fourth between color values as it progresses in
time.

The end result will have colored vertical bands with varying widths.
(and dates across axis x). I can format my data to include a start
date and end date for each color if it's needed. I suspect I'll have
to go to VBScript for this, but was wondering if there's a more
elegant solution.

I realize this resembles a stacked bar graph on it's side, but I
don't want to summarize in this way, I want to show a timeline.

Any help would be appreciated.