AmCharts - empty space in column graph if valueField does not exist in dataProvider

I am trying to create a chart using AmCharts v3 library. But I am getting an empty space between the two columns if the other Field value does not exist in the dataProvider.

Please take a look at: http://jsfiddle.net/05znyqfd/10/

The graph category 2

shows the gap between columns value1

and value3

.

How can I avoid this problem.