Millions of savers have been “robbed” of more than £9 billion in only eight years, according to a study. Those who have lost out include investors, charities and non-taxpayers.

An estimated three million investors in personal equity plans (Peps) and equity-based individual savings accounts (Isas) have lost an average of £2,000 each — £6 billion in total — and charities have lost a further £3 billion because of tax changes.

The figures, calculated for The Times by the accountant Grant Thornton, show the full impact of the decision to remove investors’ and charities’ ability to reclaim dividend tax credits.

Until 1999 investors could reclaim 20 per cent of the tax that they were due to pay on dividends generated from equity investments within Peps. That year, Gordon Brown, when he was Chancellor, replaced Peps with Isas and halved the benefit, allowing investors to reclaim a maximum of 10 per cent.

In April 2004 that benefit was removed altogether, making Isas far less appealing to investors. Charities were subject to the same rules, but they suffered a double whammy when the amount they were able to reclaim through Gift Aid at the basic rate was reduced when the basic income tax rate was cut from 23 per cent to 22 per cent in 2000.

The £6 billion loss to investors includes not only the direct reduction in income, but also the knock-on effect of the loss in investment returns had that extra money remained in the Pep or Isa.

As recently as his last Budget speech, given in March, Mr Brown had lauded the Government’s “comprehensive programme of reform to the tax and benefit system with the aims of simplifying the system, eradicating child poverty, supporting families, promoting saving, and ensuring security for all in old age”.

However, experts argue that his words and actions are at odds, with little real encouragement for savers since Labour came to power.

In fact, according to figures from the Office for National Statistics, the savings ratio — the amount of disposable income not spent — has dropped from 10 per cent in 1997 to only 2.1 per cent for the first quarter of this year, the lowest level since 1960.

Mike Warburton, who along with Maurice Fitzpatrick, of Grant Thornton, calculated the figures, said that while everyone had been aware of the loss to pension funds “no one has mentioned this loss” to Pep and Isa investors.

He added: “The impact of the removal of the dividend tax credit and the abolition of Peps has had a direct impact on savers, which is shown by the collapse in the savings ratio.”