More than 75,000 people who took out Special Savings Incentive Accounts (SSIAs) in 2001 and 2002 have since closed their accounts or simply stopped contributing to the scheme.
Records compiled by the Revenue Commissioners show that at the end of 2004, some 1, 094,294 SSIAs were "active". This compares to the total number of accounts when the scheme closed of 1,170,208, a difference of 75,914.
The figures, taken from an analysis first published in June but updated last week, suggest that some consumers have found the burden of contributing to their SSIA to be too much.
Dr Dan McLaughlin, chief economist with Bank of Ireland, said that the fall-off in participation was noteworthy because it came as many other SSIA savers were increasing their contributions.
"It's interesting because people, in the aggregate, have been topping up their accounts. It shows there are personal circumstances in which people can't maintain that level of saving," he said.
The Revenue's figures for 2004 show that the average contribution to SSIAs at the end of that year was €175.
This compared to an average contribution of €165 a year earlier, and an average of €158 at the end of 2002.
Most of the financial institutions that provide SSIAs have encouraged their customers to raise their monthly contributions as close to the maximum of €254 as possible. By contributing at this level, savers can ensure that they are getting the most out of the Government top-ups associated with the scheme.
The Government promises to add €1 to each €4 saved in an SSIA, which can either be a deposit account or an equity-based structure.
In May, figures compiled by actuarial consultants, Life Strategies showed that equity-based accounts had moved ahead of deposit accounts as the best investment option over the five-year scheme.
More recent numbers from Bank of Ireland showed that savers who had contributed €254 per month to one of its equity accounts since the scheme began in 2001 had 9 per cent more in their fund than those who took out variable-rate deposit accounts.
While it is possible to terminate an SSIA before it has completed its five-year term and withdraw the funds, this would lead to a reasonably onerous tax liability for the holder.
As well as being taxed on the Government contribution and any other gains, the holder would pay 23 per cent tax on his or her own savings, even if these came out of after-tax funds.
Account-holders who feel that they can no longer afford to save also have the option, however, of simply freezing their savings account by ceasing contributions but not withdrawing any of the cash.
In this instance, the account will mature in the normal way and only the investment gain will attract a tax liability.