tableau adjust placement of gantt bars

Question

In Tableau, I have a dual-axis bar chart of some data with their margins of error. I am using Gantt bars for the error data, and I want to overlay the error bars on top of the original data. My problem is that I can't figure out how to adjust the placement of the Gantt bars so that they are centered over the top of the original bars, with the error value displayed both above and below the bar.

I am pretty sure I need to create a Calculated Field but am new to Tableau and coding and don't really know how to go about this.

Answer 1

• Without the use of Calculated Fields, you can do this as follows:

1. Create a Bar Chart with the original data

2. You can duplicate the Bar Chart by Ctrl-Clicking the measure pill in the Rows shelf

3. You should get 2 charts one above the other now, select one of the charts from the Marks dialog, and change it to Gantt Bar

4. Drag error to the Size button of the Gantt Bar and also to the Color button

5. Now click one of the pills in the row shelf and select Dual Axis

6. Now, right click the second Axis and select synchronize Axis