Far too many people have no idea what their pensions will be worth – and many are wildly overestimating how much their savings will yield in retirement.

However, at the same time, only a small minority of people aged over 50 today are likely to be retiring with adequate resources, thanks to the massive growth of the housing market in recent years.

These new claims are made by the Institute of Fiscal Studies (IFS) in its new report, "Prepared for Retirement?", published yesterday.

Only 7.7 per cent of over-50s will have incomes of less than the level of the government's Minimum Income Guarantee, the study claims. 9.8 per cent will have an "inadequate income" as defined by the Pensions Commission.

The Pensions Commission – which is due to present its proposals for the long-term future of the pensions system in November – has previously estimated that as many as 43 per cent of pensions will not have enough resources in their retirement.

The IFS has explained this fairly gaping difference by reference to non-pension sources of wealth, notably housing and other anticipated inheritances.

"Our analysis shows that amongst older workers, at least, the fraction retiring with inadequate resources may not be as high as the first report of the Pensions Commission estimated", Gemma Tetlow – who co-authored the IFS report – explained.

However, the 9.8 per cent figure cited above nevertheless refers to 730,000 future pensioners.

More worrying, a lot of over-50s have a poor understanding of what their private pension arrangements will yield.

While more than 60 per cent of those surveyed had private pensions, over-optimism was found to be rife – with a quarter imagining that their savings would be worth 30 per cent more than they actually will be.

Worse still, one in five was "unable to give any estimate at all" of what their pension would be worth.

But is this blissful ignorance just another example of the baby boomer generation falling on its feet at everyone else's expense?

The IFS's study only looked at 4,500 over-50s – in England.

House prices in England, of course, are much higher than in Scotland, Wales and Northern Ireland.

Moreover, over-50s are much more likely to have bought their homes when they were cheap than under-50s.

Pensions awareness and levels of saving are widely understood to be much lower amongst younger people – hardly surprising when recent years have seen the collapse of numerous pension funds, mis-selling scandals, and the soaring living costs.

The Department for Work and Pensions' response to the matter of younger savers was: "It is important that people think about the kind of retirement they want and expect, and take steps to plan for that retirement."

At the same time, 2.2 million of today's pensioners are living below the poverty line, according to the "grey vote" lobbying body, the National Pensioners Convention.

Demanding action on pensioner incomes as a "matter of urgency", the NPC is staging demonstrations today outside the Houses of Parliament, the Scottish Parliament in Edinburgh and the Welsh Assembly in Cardiff.