Income inequality in Ireland has fallen over the past three decades, but measures of poverty remain high for lone-parent households and those without a job.

These are the main findings in new research published by the Economic and Social Research Institute today.

In a report entitled "Poverty, Income Inequality and Living Standards in Ireland", the authors track changes in disposable income over the years from 1987 to 2019.

The report finds that disposable incomes, which is income after taxes, social welfare payments and pensions, rose by an average 3% per annum over those years.

Despite a "lost decade" from 2007-2017 following the economic crash, growth in disposable incomes was "broad-based and progressive", the ESRI said.

Incomes rose by 3.6% for the lowest earning 20% of the population while they rose by 2.7% at the highest 20% level.

The report finds that a key measure of income inequality was 16% lower in 2019 than it was in 1987 - its lowest level in three decades.

The report says Ireland's experience in lowering income inequality differs from most other OECD, or advanced, economies.

The country's progressive tax system, which taxes those on higher incomes more than the lower paid, is one of the factors behind this.

Today's report also finds that rates of income poverty have fallen sharply, by a quarter, and rates of material deprivation by half over the years from 1994-2019.

However, it also finds a high incidence of low living standards among lone parent families. It also says that a higher incidence of income poverty is closely linked to the absence of anyone in a household in paid work.

This is in contrast to the UK, where poverty "has increasingly become an in-work phenomenon."

The report suggests that because of this, the social welfare system may be more effective in tackling poverty in Ireland than increases in hourly wages.

However, it also warns of the risks of increasing poverty if people do not return to jobs affected by Covid-19 restrictions.

Barra Roantree, an ESRI economist and one of the report's authors said, that Ireland is one of the few European countries to have experienced broad-based growth over the past three decades.

"Disposable incomes rose by more for lower-income than higher-income people, leading to big declines in income inequality between 1987 and 2019," the economist said.