The Financial Services Authority (FSA) is to consult on reducing its projection rates after independent research supported the move.
A study by PricewaterhouseCoopers (PwC) looked at the rates which apply to retail investment products such as personal pensions and life products.
The research supported a reduction in the current 7% intermediate projection rate and in the adjustment for tax-disadvantaged products.
PwC recommended the figure should be brought down to within the range of 5.25% and 6.5%, adding the 1% adjustment for tax-disadvantaged products should be reduced to 0.5%.
The products for which the FSA currently produces projection rates includes endowment policies, maximum investment plans, stocks and shares ISAs and personal pension plans.
Peter Smith, head of investments policy at the FSA, said: "It is crucial that projection rates are set at a realistic level so that investors are not misled.
"Today's independent research indicates that our maximum projection rates should be reduced. We are seeking views on the range of rates so investors receive a reasonable indication of what they can expect from their investment."
The current rates are based upon an asset mix of 67% equities and 33% bond investments. Firms are required to revise these rates downwards where the asset mix of a product makes it unlikely to achieve returns in line with these rates.
A previous review, conducted by PwC in 2007, concluded that the existing rates remained valid.
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