Accessible Data Storytelling with Power BI: Design Concepts and Accessible Colours

Paul Waller 30th November 2022

Accessible Power BI Data Storytelling

We've created a report that uses open data published by the World Bank to explore global trends in wealth & health. This report has been published to the Power BI community data stories gallery.

The video below walks through the report from a visual design perspective. Red–green color blindness affects up to 1 in 12 males (8%) and 1 in 200 females (0.5%)^{1 2}. It reinforces how important concepts such as branding, accessibility, visual design, colour palette choice. interactivity and page layout are to allowing users to engage successfully with a report.

You can find the report on the Power BI Community Data Storytelling Gallery.

You can also watch a high-level walk-through of the report: Data Storytelling with Power BI: The World Bank World Health and Wealth Report

Transcript

This is a Power BI design demo where we walk through our latest custom World Health and Wealth Power BI report, showcasing an array of design concepts from branding, color and logo placement in respect to clear areas, layout and page composition for clean and clear page design, interactivity for guided navigation throughout the report.

We are building a data story to extract meaningful content to help users easily discover insights using open source data provided by the World Bank Open Data Project. Also, we're experimenting with an accessible color palette to assist users with color vision deficiency, or colorblindness, as well as exploring other methods to differentiate and visualize data. Resulting in an engaging and inclusive experience.

So starting with our cover page, we have sourced a creative comments image, which has been inserted as a background. This gives the appearance of a full bleed image. We set up PowerPoint templates to enable non-creative members of the team with the autonomy to add and amend simple items of image content without hold ups.

In the top right hand corner, we have our company branding. Next we have our report title. We have added each line separately to give us more control over the leading. Below is the World Bank Data logo as an acknowledgement to the data source, and then to the right of our title, we have our button to begin our guided navigation, which takes us through to the introduction page.

You'll see a grid in the background. This grid forms a foundation of all layouts throughout this report, and it is one of the first elements that we set up at the start. As we design and build our report, we can turn with this on and off with the transparency slider. This helps us maintain consistent alignment and spacing across all of our layout.

On the left, we have shifted the title to occupy the first column vertically. We then use a graphic divider to split the title and image area. For the image, we have designed an indicative graphic that represents families globally. This has been paired with our theme colors, designed for accessibility taken from the JSON [file which you can use to set the colour palette for Power BI].

This also helps us bring those colors through to other areas of the report for creative continuity. Between the contextual image and our introduction text, we have another divider. Our introduction text provides a brief outline of the data story where we have sourced the data set and the topics we are exploring.

In this report, across the top, we have our branding adhere into clear areas. In the bottom right, we have our call to action buttons, inviting the viewer to begin their journey through the. By clicking the overview button or referring to the documentation page where we hold all our image credits. I'll just move the transparency of our grid to 100% to remove the grid from view and click the overview button to continue our journey into the report.

The overview page forms the hub of the guided navigation linking all of the subtopics. Each image has been set up as a button displaying one high level metric, topic, title, contextual image, and under the info icon, we have added a description on hover.

This marks the start of our data story comparing the health of a nation measured in life expectancy against the wealth measured by gross domestic product per capita. Ultimately, we want to determine whether a country's GDP influences the average life expectancy of its population. And understand the primary factors at play influencing this relationship. You can see a more in depth view of this in our data story video.

We will start by looking at the countries and region section.

First, you will see have a map of the world showing all countries within this report, color coded by continent and utilizing our colorway. To the right of the map, we have a search box to easily find a particular country followed by a country list which the viewer can scroll through. At the bottom, we have a button that is disabled until a country is selected.

If we hover over the map, we can release high level information about a particular country in a custom tooltip. However, if we wanted to speed up the process and drill down into a particular country, we can do this via the search field. This will isolate the country in the list and on the map with its region color.

You'll notice that as we select the country, the country scorecard button is now active and we can find out more about the country's life expectancy versus GDP. On the scorecard page, we have a strong header to indicate that this page is different from the others. It services more detailed metrics from the country's official title, income banding, the data story widget showing continent currency.

Overall population life expectancy and gdp. This is echoed in the charts below. In the health chart. We track the average life expectancy shown as an area chart with a short dotted line below. We track the wealth and GDP per capita shown as a line chart and a dash. To the right, we can see the country's location and bordering nations.

We can zoom out on this to get a wider perspective of its location. Below this, we track the population growth or decline shown as an area chart with a solid line. The lines we use are as important as the color palette we have develop. As each line style represents the same metric as we go through the report, we go back to the overview page and look at another topic.

In the health section, we have utilized a series of area charts looking at the median health color coded by region, showing life expectancy from birth in years. When we look at the distribution of health, you'll notice we have top and tailed the min-max life expectancy with our dotted line. From the previous section, adding muted dash lines to the metrics in between, while it's also utilizing different marker shapes for better legibility.

On the health gap chart, we have applied the same system to differentiate the content. If we go back to our overview page, we can see how this design approach works in the wealth section. We have changed the chart slightly to use line charts, looking at our median wealth color coded by region, the distribution of wealth by decade with our dashed and dotted lines, and we can see the wealth gap between the richest and poorest countries.

If we return to our overview page, there are a couple of sections we'll let you explore. However, we have covered the design aspects that we set out at the beginning from branding, layout, interactivity, data stories, and our exploration into developing an accessible color palette accompanied with other methods of visualizing.

An important element for consideration when we develop our reports is not overloading the pages, so we look for clean, clear layouts to allow our content to breathe whilst conforming to the foundations of our grid.

If you have any comments, please get in touch. All feedback is welcome, and thank you for watching.