Every year in France, all road accidents with at least one vehicle involved and at least one person needing medical care are registered by the authorities. The official statistics for the year of 2023 was published in October 2024. I decided to run some exploratory data analysis to uncover insights. It turned out I found an age paradox!
Methodology: The publicly available datasets (see data source below) are in in csv format per year and per user, place, characteristics and vehicle. After importing the csv files to Power BI, I performed data cleaning and transformation in Power Query.
After data preparation, I started the analysis in Power BI. I started by creating explicit measures to calculate totals and subtotals as well as risk ratios. For example I used this DAX formula to calculate the total users with major injuries
Total Major Injury = CALCULATE(
COUNT(users[user-ID]),
users[severity] = "Major injury"
)
and then I referenced that measure to calculate the risk ratio:
Risk of Major Injury = [Total Major Injury] / [Total Users]
Using the AI visualization called Decomposition tree, combined with a line and column chart and some other helpful visualizations (like cards, tree maps, slicers etc.) I discovered that the risk ratio for kids and teenagers users is higher than for adults.
Binning: I used a binning technique, creating age groups in power query to analyze the age data by groups and reduce granularity.
Page layout: My target group will mostly access this project on mobile devices, I therefore choose a mobile friendly design with a portrait page canvas in Power BI.
Color schema: Dark mode was recently released in Power BI (Sept. 2024) and presented at the Stockholm Fabric Conference in October 2024, that’s why I selected a dark mode design and combined it with a color palette generated from Adobe (see ressources below).
Visuals: The main insight in this project is the age paradox, with kids and teenagers running the highest risk to get injured, despite representing a minority of road users. I selected a line chart as the main visual to illustrate this paradox ans show the risk changing over ages.
The second visual element is a 100% stacked column chart, showing a comparison of severity of injuries between age groups.