I assume the Deputy is referring to retirement relief from Capital Gains Tax on the sale or transfer of assets used in a business or farm.
I am informed by the Revenue Commissioners that it is not possible to accurately estimate the potential Exchequer cost from changing the age limits and relief thresholds in respect of retirement relief as it would depend on future transfers of assets and businesses. From Capital Gains Tax returns for 2016, which is the most recent year available, the number of individuals with claims in respect of retirement relief in excess of €3 million, irrespective of the age of the individual, was less than ten.