"I haven't seen action like this since the days of Russian problems back in '97," he said. "These are scary times. I've been trading foreign exchange for a long time. These things frighten me, and I've got to tell you: I'm cutting my positions way down just because of the volatility's so large."
On CNBC's "Fast Money," Gartman said that he had backed off moves of $2 million to $5 million in the yen trade, opting for smaller $500,000 to $1 million "just to keep the volatility to something that is reasonable."
"I mean, these are very scary times," he added.
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Gartman said that he would continue to be "very, very bearish" of the yen, expecting the Japanese currency to trade 125, maybe 150, to the U.S. dollar over the next couple of years.
"But again, I traded dollar-yen back in the 1970s when it traded 285, so to think it going to 125, even 150, is not that large a move for me over a long period of time.
Gartman noted that he preferred to trade other currencies against the yen.