New figures from the Central Statistics Office show that the median weekly income of employees who received Covid-19 income supports fell by 12% in the year to the third quarter.
This compared with a rise of 5% for non-recipient employees, the CSO said.
The CSO's new "Impact of Selected Covid-19 Income Supports on Employees 2020" examines the extent to which workers' weekly earnings and income were affected by the Covid-19 pandemic.
It also looks at the impact income support schemes had on the income of recipient employees.
Of those receiving income support, the lowest earning 20% of workers saw their median weekly income rise by 35.4% while those who received supports that were in the highest earning 20% saw their median weekly income fall by 22.7%.
The CSO said that workers under the age of 25 had a reduction in their median weekly earnings of 22%, compared to an increase of 3.2% when income supports were included.
Of those workers who received Covid-19 income supports, the groups that were least negatively affected by the outbreak of coronavirus, relative to their income in 2019, were women, those aged under 25 and low earners.
The CSO said that median weekly earnings of all employees combined, which excludes Covid-19 income support, fell significantly during the second and third quarters for all demographic categories.
"However, when Covid-19 income supports are included in employee income, the scale of these falls is reduced and for some categories their income increased in the period," it added.
