I recently worked on a project where our client wanted to visualise the distribution of a measure across different UK regions. However, regions, perhaps due to their ambiguity, are not automatically mapped by Tableau. Thus, I thought I would share my solution to this issue so that anyone can go forward and analyse across UK regions with less difficulty.
The Issue
Above shows a map of all UK Counties (Left) and Postcodes (Right).
While Tableau can visualise a map of the UK at a county and postcode level, it can't automatically group these counties, or postcodes into larger regions. As such, you couldn't quickly visualise how sales differed between the South East and North West of the UK.
The Solution
In order to visualise UK regions within Tableau, you have to first find a dataset containing all UK Postcodes (one can be found within the linked Tableau Workbook below). After sourcing your data you need to create a group within your postcode field.
The next step, is to manually assign each post code to a group (region). While our dataset only contains the beginning half of each UK postcode, this still leaves us to assign 2,568 postcodes into groups. The quickest way I found to do this was to select Find -> [Type postcode letter(s)] -> Find All. This reduced my work from 2,568 postcodes down to 124.
Once complete your group should look something like this. Note, the benefit of creating your own region groups is that you can quickly place postcodes into different regions, for example, our client wanted to place some areas of East England into the South East instead.
Please find the link to the Tableau Public dashboard below. Feel free to download and copy over the region worksheet into your own work, as it will automatically bring the region groups, and postcode data, into your workbook. I hope that this blog and workbook can save you the time I spent creating all of these region groups.