For chart syles, why doesn't color order match series order?

[AMiller]

I applied a chart style to several charts in the same workbook, which each
link to the same three separate excel files. Each series is named for one of
these three files, and they are in the same order in all charts, however, the
order of the colors is different in each of the charts, and some even have
the color that the style would use for a fourth series even though there are
only three. I would like the data from each source file to be the same color
on all plots so it's not confusing to the viewer when switching between
charts in a presentation.

How does Excel decide which series gets which color if it's not determined
by series order? Is there a hierarchy (something like "series order") that is
hidden? How can I change this so that the "color order" is the same in all
plots? I could of course do this by manually each series, but would prefer to
understand what's going on.

 

[Jon Peltier]

You've touched upon one of the mysteries of our time. The order of
colors in an Excel chart is related to when each series was added to the
chart. If you change the plot order, you still haven't changed the order
that the series were added. To make it confusing, if a series is deleted
from the middle of the order, the next series added takes its place in
the middle of the order.

You probably spent a lot of time on one chart, tweaked it, added and
removed series until it was just right. Then the others you assembled
much more quickly without all the false starts. So they don't all match
up as your eyes tell you they should.

The way to make the charts all the same is to carefully build them in
parallel, adding series to the charts in the same order.

This description is for Excel 97 through 2003. There are enough other
mysteries with Excel 2007 charts, that I haven't gotten to such minor
trivialities as the color system.

- Jon