It sounds like the issue you are experiencing is due to the fact that you added a dummy set of data at the beginning of your data series. This can cause the first bar to appear smaller than the others because it is being compressed against the y-axis.

To fix this, you can adjust the minimum value of the x-axis so that it starts at the first category label instead of at zero. Here's how to do it:

1. Right-click on the x-axis and select "Format Axis" from the menu.
2. In the Format Axis dialog box, select the "Scale" tab.
3. Under "Minimum," select the "Fixed" option and enter the value of the first category label in your data series.
4. Click "OK" to close the dialog box.

This should adjust the spacing of your bars so that they are evenly spaced and the first bar is not compressed against the y-axis. If you need to adjust the maximum value of the x-axis as well, you can follow the same steps but select the "Maximum" option instead of the "Minimum" option.