Today Idiro has published a data visualisation dashboard (here) allowing you to explore the 2016 NCT test results. 

Update 21/8/17: The Sunday Independent ran a story yesterday on Idiro’s dashboard – see here 

Update 30/8/17: Our dashboard has been picked up by many other media including RTÉ:

About this dashboard and the data

This interactive report is published by Idiro Analytics as a demonstration of our data visualisation capability. The data used is published by and covers NCT tests conducted in 2016. The data covers the first NCT test that each car underwent in 2016 – data has not been published on retests for cars that fail.

The data is filtered to show only the twenty most popular makes of vehicle tested in 2016, and for each of these, only models with at least 1000 tests carried out. This was necessary because to show every make and model of car tested would make the dashboard unusable. As a result, from the total 1.4 million test carried out in 2016, 1.1 million tests are represented in this dashboard.

If you wish to examine the data further or want to look at makes / models of cars that are not shown in this analysis, the full dataset is available for download at

How to use this dashboard

Pro tip: To reset all your filters and return to the original screen, click your browser’s refresh button.

Pro tip: To compare different car brands, press CTRL + click on the type of makes you want to filter in the bubble chart “Overall Popularity & Passing % of Model”. 

The RSA provides the ‘Year of Car’ of each car tested.  You can filter by the age of cars using this slider. 

If you want to see cars from 2010 or before that were tested in 2016, you simply drag the end buttons in the slider (at the top) over to the desired year.

As the year changes, so do the interactive maps. This bubble table shows the top 20 most popular car models with a 2010 or older registration tested in 2016 that passed first time.

The bubbles indicate how popular that model is, and the colour of each circle indicates the pass rate – from deep blue (high pass rate) to deep red (low pass rate).

For example, we can see below that for vehicles registered in 2010 and older. Toyota is the most popular and has a high pass rate in 2016.

In the next graphic to the right, ‘First time pass rate by model’, you’ll see the different Toyota models that were tested.

In the next table ‘Model Popular Model & Age’, you’ll see the most popular models in the Toyota age range of the models tested.

Although the Prius has the highest pass rate in the Toyota model, it isn’t the most popular make, Corolla is the most popular.  As you scroll down the interactive map, you can see the failure rates of each car that was tested in the NCT and what the cause of the failure was.

You can filter what cars failed on by category or you can choose to see total which will show all the categories on the ‘First Time Failure By Year On’ drop-down menu.  The image below displays blue bars which indicate the units tested in each year and the red line graph shows the failure percentage rate. Remember that pass/fail thresholds can vary according to the age of the car.

As you scroll across, you’ll see the ‘First Time Failure By Category’ table. This table shows each category that the NCT test each car.

This graph displays what caused Toyota cars to fail their NCT. 

Here’s the link to the dashboard:!/vizhome/NCT2016Top20MakesResults/NCT2016-20MostPopularMakes

To contact Idiro about this blog post or about how Idiro’s analytics can help your business, drop us an email at  To download the source data from, click here.  

Recommended Posts