I downloaded the population for each county for the years 2011 and 2016. I decided to do both years so the daisy chains could be used as a comparison. The user can see the increase/decrease of road deaths in these years.
The reason for using years 2011 and 2016 is that these are the years that the population census was carried out. There was no data for the years in between 2011 and 2016. The data sets were downloaded from CSO. The images below are screenshots of the population. The population at the top where it says Population 2 is the 2011 figure and the below that is the 2016 figure.