COVID-19 Insight: Mobility During the Pandemic Week Ending 31 December 2020

Key findings

• The Staying Local Indicator (SLI) shows the lowest percentage of the population (51.7%) staying within 10km of their home each day for the week ending 24 December 2020 – the highest level of mobility at any point during the pandemic or throughout 2020
• One week later, the week ending 31 December 2020, the percentage of people staying local had increased with almost 58% of the population estimated to have stayed within 10km of home each day
• The SLI peaked during the first wave of the pandemic, when 76.7% of the population were estimated to have stayed local each day for the week ending 15 April 2020
• During the second wave of the pandemic the SLI peaked during the week ending 04 November 2020, when 62.9% of the population were estimated to have stayed local each day
• In January and February, prior to the onset of the pandemic, on average 56.5% of the population were estimated to have stayed local each day
• Counties with high urbanisation levels tend to have greater numbers of people staying local, reflecting population density and proximity to essential services such as schools and shops

The Staying Local Indicator – SLI

The Staying Local Indicator (SLI) provides daily estimated percentages of county populations that have stayed within 10km of home, averaged over the preceding seven days.

The Staying Local Indicator is based on statistical analysis of anonymised, aggregated, mobile phone activity records. Data from Three Ireland is collated from anonymised data sets at a macro scale, aggregated at Electoral Division and provided to the Department of Health. The scope of the arrangement between Three Ireland and the Department of Health is limited to informing the Government response to the COVID-19 pandemic only. This data feeds into wider selection of data used as part of the COVID-19 response. Only aggregated statistical data is provided to the Department of Health. No personal data is provided.

The CSO receives and manages this data on behalf of the Department of Health. Only aggregate data is provided by Three Ireland, and at no time do either the Department of Health or the Central Statistics Office have access to personal data or individuals’ movements. The outputs from this analysis provide important insights for decision makers and the public in the midst of a global pandemic.

The impact of Government restrictions on travel are clearly visible at National and county levels.  Marked rises and falls in the SLI visibly reflect the imposition and relaxation of movement restriction policies at key dates throughout the year.

County variations in the SLI

Propensity to stay within 10km of residence tends to differ by county, as movement is impacted by local circumstances and conditions, such as access to services and levels of urbanisation.  For example, Dublin, with a high level of urbanisation, consistently shows the highest percentage of persons staying local, while Roscommon and Mayo, with low levels of urbanisation, have the lowest percentage of persons staying within 10km of home. 

Dublin showed the highest percentage of persons staying local of any county for the week ending 31 December, at 66%. This compares to the more rural counties such as Galway (48.7%), Mayo (48.2%), and Sligo (49.8%) with less than half the county population staying within 10km of their usual place of overnight residence.¹  The State weighted SLI average week ending 31 December was 57.4%.

¹This text was updated after publication on 14 January 2021.

Week-on-week change in the SLI at State and county level

Comparisons of week on week changes at State and county level are presented in Table 1.1, Map 1.1 and Figure 1.2 below.  All counties saw reduced mobility levels when comparing the week ending 31 December 2020 with the previous week. This corresponded to a 5.7 percentage points decrease in mobility for the State.

• County Monaghan saw the biggest percentage change in persons staying local (11.7 percentage points) when comparing the week ending 31 December with the previous week, from 45.4% to 57.1%.
• County Dublin saw the smallest percentage change in persons staying local (1.6 percentage points). Some 66.0% of the population stayed local in the week ending 31 December compared to 64.4% in the week previous

Go to: Methodology and Notes