For some reason many investors, particularly institutional types, like to invest the first week of a year, quarter and month.

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One reason is that their usual sources of capital, institutional investors, hitherto often trapped by regulations requiring them to keep a certain proportion of their assets in their domestic currency, are now, thanks to the euro, able to spread their wings.

ECONOMIST: European capital markets

Another reason for the popularity of index funds, especially in the institutional market, is that comparison to widely available benchmarks makes performance measurement so easy.

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Another reason for greater openness is that hedge funds are trying to attract more money from institutional investors, not just the rich individuals who have been their traditional source.

ECONOMIST: Hedge funds

The main reason why margin requirements make little difference to share prices is that most prices are set by institutional investors, and not, as popular myth suggests, by crazy day traders.

ECONOMIST: Marginal differences