Mr Cameron explained: “Aegon analysis of inflation and interest rates over the last 50 years shows that people are losing more purchasing power now than at any other time over the last 44 years.

“You need to go back to November 1977 for as bad a situation, when inflation was at 13 percent, or six percent above the base rate of seven percent.

“When inflation was as high as it is now, in early 1992, the base rate was sitting at over ten perent.

“That meant cash savers achieving this return were still beatng inflation and seeing their purchasing power increase by around three percent a year.”