Figures from the Department of Finance show that the country's higher earners paid an extra €38.5m in tax during 2016, thanks to the restriction on certain tax reliefs.

These restrictions, which were introduced first in 2007, are aimed at reducing the number of reliefs a high earner could use to limit their tax bill in any given year. 

Before their introduction, high earners - by means of the cumulative use of various tax incentive reliefs - had been able to reduce their tax liability to very low levels or to zero. 

The restriction works by limiting the total amount of specified reliefs that a high income individual can use to reduce his or her tax liability in any one year.

"The High Income Earners' restriction is working as intended and is working well," the Finance Department said. 

The figures show that 149 high-income individuals with an adjusted income of €400,000 or more paid an average effective tax rate of 30.1% on the combination of adjusted income and ring-fenced income. 

When USC is included, their average tax rate was 40.9%. 

The Department said the additional tax collected from these 149 taxpayers was €25.8m, representing an increase of 175% on the tax that would otherwise have been paid if the restriction had not applied.

It also noted that 54 individuals with adjusted incomes of €400,000 or more, who would not otherwise have paid tax in 2016, were brought into the tax net for that year.

The report also shows that 372 high-income individuals with an adjusted income of up to €400,000 paid an average effective tax rate of 19.09% on the combination of adjusted income and ring-fenced income. 

When USC is included, their average tax rate is 28.61%.

Finance said the additional tax collected from these 451 taxpayers was €12.7m, representing an increase of 242% on the tax that would otherwise have been paid if the restriction had not applied.

It also said that 164 people with adjusted incomes of up to €400,000, who would not otherwise have paid tax in 2016, were brought into the tax net for that year.