A valid criticism of conventional tracker bonds is that money is tied up for sometimes as long as six years a daunting prospect for some savers. Unfortunately, encashing a tracker early puts the capital guarantee at risk.

Standard Life's latest addition to its Diamond Tracker series provides a capital guarantee, and also guarantees the surrender value terms over the last two years of this five-year, five-month bond. The amount varies depending on the unexpired time left on the account. This latest Diamond Tracker, which tracks the performance of the Eurotop 100 (Europe's top companies) and the S&P 500 offers two investment options: the Capital Option returns all the capital plus up to 76 per cent of performance growth, while the Growth Option offers a guarantee of 93 per cent of capital back plus 100 per cent of any growth achieved. The minimum investment is £5,000 and the closing date is May 22nd.