The easing of restrictions on inter-county travel led to a sharp increase in car traffic volumes, new figures show.

The numbers of cars on the road increased considerably in the week beginning May 10 compared with the previous week, figures from the Central Statistics Office (CSO) show.

In its latest Transport Bulletin, the CSO shows the impact of the latest Covid-19 restrictions on traffic volumes and the number of journeys taken on public transport.

The bulletin is compiled using data collected by Transport Infrastructure Ireland, the Road Safety Authority, the National Transport Authority, Dublin City Council, the Office of the Revenue Commissioners and the Department of Transport.

The figures show the volume of cars on Irish roads has been rising slowly since the start of the year following the move to Level 5 restrictions in December and more rapidly since travel restrictions lifted on May 10.

The easing of travel restrictions is also reflected in the greater use of public transport.

Latest available data shows the total number of rail and bus journeys are at their highest since the beginning of 2021.

Statistician Dr Nele van der Wielen said: “The Covid-19 restrictions continue to have a significant influence on traffic volumes, but the data also reveals an increase in travel associated with the recent lifting of restrictions.

“On May 10, the country-wide travel restrictions changed from a 20km radius or anywhere within your own county to anywhere within Ireland.

“Car traffic volumes increased significantly in the week beginning May 10 compared with the previous week.

“That week saw an increase of 18% in car traffic volumes in selected regional sites.

“Car traffic volumes in the week beginning May 24 were nearly twice as high in regional locations than in the same week of 2020, however volumes were still 17% lower than the equivalent week of 2019.

“The lifting of travel restrictions within Ireland is also reflected in the increased usage of public transport.

“Latest available data on the total number of rail and bus journeys indicates they are now at their highest level since the beginning of 2021.”

Dr van der Wielen also said that Covid-19 continues to have a “major impact” on airport passenger numbers, however, the number of passengers travelling through Dublin airport in April 2021 grew by 9% compared with the previous month.

Meanwhile, the impact on HGV traffic of Covid-19 restrictions has not been as pronounced as for cars.

In April and May 2021, heavy goods vehicles (HGV) traffic volumes in both regional and Dublin locations were above 2020 levels.

In general, from June 2020 onwards HGV traffic volumes exceeded 2019 levels, particularly in the lead-up to Christmas.

Since the beginning of the year, HGV traffic volumes in both regional and Dublin locations have remained below January, February and beginning of March 2020 levels.

However, this pattern has since changed.

In April and May 2021, HGV traffic volumes in both regional and Dublin locations were above 2020 levels.

The latest data available, for the week beginning May 24, shows HGV traffic volumes are 18.9% higher in Dublin and 20.8% higher in regional sites compared with the same week in 2020.

The number of new cars licensed in May 2021 rose by 5,847 vehicles compared with May 2020, but there were 1,789 fewer vehicles than May 2019.

The number of rail and bus journeys are at their highest level since the beginning of 2021.