It claimed six months of volatile stock markets have damaged returns and warned investors' statements will show how global financial difficulties have affected them.
"This is the first time for a number of years that these regular statements – which are sent out every six months – have delivered such bad news," the paper has claimed.
It reviewed a selection of funds' performances from the last 12 months and revealed the worst performing was Scottish Widows' SWIP UK Real Estate.
In most cases falls have occurred in the last six months and most "equity funds had benefited from a summer of growth," the paper commented.
New rules were introduced yesterday, which allow individuals to invest twice as much in stocks and shares ISAs.
