Dennis Gartman sees stocks dropping another 10%-15%

These broken trendlines signal end of bull run: Gartman
These broken trendlines signal end of bull run: Gartman   

Closely followed investor Dennis Gartman on Friday put a timetable on his call that U.S. stocks are in a bear market, after Wall Street recorded its worst four-day start to a new year ever.

"This opening rout in the opening several days of the year has broken whatever last residual hope the bulls might have had," Gartman told CNBC's "Squawk Box," one day after he said a bear market has started.

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The editor and publisher of "The Gartman Letter" said he believes there could be six or seven months of downside ahead. Bear markets happen when declines exceed 20 percent or more from the most recent record highs.

"I think after what's happened in this opening week, the propensity of people to step up and buy has reduced," he said. "And the propensity to step up and sell has increased."

Thursday's sharp slide pushed the Dow Jones industrial average and the Nasdaq composite index into correction territory. The S&P 500 index was about 1 percent away from a correction, defined by a decline of at least 10 percent from all-time highs.

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'Safe harbor' cash is not a bad investment now: Gartman
'Safe harbor' cash is not a bad investment now: Gartman   

The stock market could drop another 10 or 15 percent from here, said Gartman, who tends to trade more in the moment, rather than taking a long-term position on the markets.

In October, he reversed his bearish stance, only to be proven incorrect as market weakness continued amid uncertainty over the timing of a Federal Reserve interest rate hike hike, which eventually occurred in December.

On Friday, he advised investors that "cash will be a wonderful safe harbor," adding that owing a little gold and some Treasurys also seem like good ideas in this environment.

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