"US liquidity concerns following the Fed minutes looks like the pin which will burst the recent bubble in equities, " said Mike McCudden, head of derivatives at Interactive Investor.

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We have been at zero percent since December 16, 2008 with recreated bubbles in commodities and equities with the housing bubble still deflating and with toxic mortgage securities still sloshing around the banking system.

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The other rare instance where values ventured so far from the trendline was during the Tech bubble (when equities were overvalued), but that is the exact opposite than what we have today.

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"The Nasdaq 100 will test September's lows in late May, but in the fall it will actually set new lows, " says Jimerson, who cites a declining U.S. dollar and a burgeoning real estate bubble as ominous signs for equities.

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Indeed, continental European savers' appetite for equities never recovered from the bursting of the dotcom bubble.

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But what if the bubble this time is in government bonds, not equities?

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The current poor performance of stockmarkets reflects, of course, a reversion to the mean after the excesses seen during the dotcom bubble, when the rolling 25-year annual return of US equities reached a remarkable 16%.

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Robert Shiller, a Yale economist who has presciently issued warnings about overpriced equities and houses, has already suggested that farmland might be the subject of the next bubble.

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