Change the spacing between data markers in bar and column charts
Click a data series in the chart you want to change. You need to select only a single data series to change the overlap or spacing of all data series of the same chart type.
On the Format menu, click Selected Data Series, and then click the Options tab.
To change the overlap of the data markers in each category, enter a value between -100 and 100 in the Overlap box. The higher the value, the greater the overlap within the category.
To change the spacing between categories of data markers, enter a value between 0 (zero) and 500 in the Gap width box. The higher the value, the greater the distance between each category.