Excel doesn’t always get it right when it automatically assigns one set of labels to the X-axis and the other to the Y-axis. For example, normally in a chart like the one below the months would be on the X-axis. In this case Excel put the sales regions on the X-axis. Now how do you fix that?
Excel examines two main parts of data layout before making a chart. It looks at the top left cell to see if it is blank. If it is, then it assumes there are labels across the top and down the left side. If the top left row is filled, then it assumes there are only labels across the top. (See the tip ?? <Troubleshooting Problems in Excel Charts: X-Axis Doesn’t Chart Correctly>.)
If Excel assumes there are labels across the top and down the left column, then it assumes that the longer of these two is the X-axis. In this case that is the wrong assumption. Gotcha!
It’s pretty easy to fix,
1. Select the chart.
2. On the Design tab, in the Data group, click the Switch Row/Column tool as shown in the figure below.
The chart and legend will change their orientation so months are across the X-axis and regions are on the Y-axis as shown in the figure.