A survey by Moneyfacts has revealed Abbey's variable rate ISA as the top-performing variable rate Mini Cash ISA this year.
The Moneyfacts Mini Cash ISA Survey 2005, which examines the projected value of £3,000 invested on 6th April 2004, found that the Abbey variable rate ISA gave a return of £3,155.27.
The average return this year is £3,137.61, showing an increase on last year's figure of £3,111.73.
Mutual ISAs took fourteen of the top twenty places, with the two-year fixed rate ISA from West Bromwich Building Society coming top with a return of £3,160.50.
This ISA was only available to existing customers, however, and is now closed to new investors.
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