How do I change the colors of individual bars, in a bar chart of in Apple's Numbers 3.2.x
In experiencing this problem, Numbers always treated all of my bars as one series (not sure what planet that makes sense on, but whatever). You need your data treated as separate series so that you can apply a color to each series.
With the chart selected, click the Edit Data References button that appears over the chart. Then, look in the lower, right-hand corner, there will be a little tiny slightly darker gray on light gray button labeled "Plot Rows as Series" (or "Plot Columns as Series"). Change this setting and you should have separate series for each of your data points, which will allow you to change their colors.
Note that none of this is in the documentation.
As of Numbers 3.6 (possibly earlier), that's the lower left-hand corner.
I found this page to be helpful - I had wanted to color the bars for control cases differently than the normal ones.
I hate to say this, but still have to say the previous answer is quite misleading, because it is only working if there is only 1 data point per series.
I believe here the following is the real way of doing it correctly. 1. split data by column (or transpose the table if you want) 2. define each column as different series 3. change gaps in order to optimize alignment (you may try different number, then you'll find the bars are not evenly distributed as 0% and 999% setting).
Screenshot below for setting/format.