An estimated 66.7% of the population stayed local (within 10k of home) during the week ending 12 February, according to the Staying Local Indicator (SLI), a seven-day rolling average released by the Central Statistics Office (CSO) this morning.

All counties showed SLI decreases from week ending 5 February to week ending 12 February, ranging from 0.6 percentage points (Waterford) to 2.9 percentage points (Roscommon), indicating some relaxation of mobility behaviour.

Urbanised

Dublin continues to be the county with the highest percentage of the population staying local (79.7%) on the week ending 12 February, reflecting its urbanised nature and access to services, compared to other counties.

This is the third of an insight series on mobility produced by the CSO.

The CSO says the estimates are an example of how aggregate data can be used to indicate mobility during the pandemic and whether Government restrictions impact behaviour.

The Staying Local Indicator (SLI) provides daily estimated percentages of county populations that have stayed local for example within 10km of their usual place of residence, averaged over the preceding seven days.

Anonymised data sets

The SLI estimates are 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 (ED) and provided to the Department of Health.

The SLI is not an exact measure, but a general indication of what percentage of the population is staying local.

Mobility patterns

With 2.4 million users as of August 2020, Three Ireland commands a 35% market share.

The SLI is premised on the assumption that mobility patterns extracted from the anonymised data of Three Ireland mobile users are broadly representative of those of the wider population.

Three Ireland incorporate detailed population statistics from the Central Statistics Office (CSO) as part of this process.

Aggregates

The statistical aggregates are provided to the CSO with the permission of the Department of Health and under the terms of their agreement with Three Ireland. Only aggregated statistical data is provided to the Department of Health. No personal data is provided.

The CSO receives and manages the data on behalf of the Department of Health.  The data is deposited by Three Ireland on secure CSO servers.