The SuperTrust structure had share creation and redemption characteristics of an open-end fund and the trading flexibility of a stock.

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The idea was to first convert this small, open-end fund into a closed-end.

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The four iShares index funds (see table below), issued by the Global Investors unit of Barclays (nyse: BCS - news - people ), sport a rock-bottom expense ratio of 0.15 versus open-end bond fund averages of around 1.00 and the 0.20 charged by low-cost leader Vanguard.

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