When you create a column chart, you may want to change the gap size between the series, normally to remove the gap from the column chart. So how do we get Excel chart columns with no gaps in the chart below?

YouTube Remove gaps in Excel charts
In order to do this you can right click on any one of the data series and choose Format Data Series. You will notice that one of the options is Gap Width and the default is 150%.
You can play with this gap width but the extreme would be to remove the gap completely (make it 0%) as shown below.

In this case it is important to note even though we only chose one series, all the series on that axis (the primary axis in this case) HAVE to have the same gap width. You can’t have one series having no gap and another series on the same vertical axis having a gap. In order to generate that appearance you need to trick Excel.
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