Several factors are currently in play concerning the dollar, yen yield, which could push the U.S. dollar down in the short term.
With a wider spread the Japanese will invest in the U.S. dollar, while a shrinking spread causes them to place their money elsewhere.
On Thursday, March 1, the spread between U.S. and Japanese note yields (yen against the dollar) hit 0.29 percentage point, the widest it has been since August 2011.
The risk for the dollar, yen correlation is the low yields in the U.S., which are expected to remain in place for some time, combined with a possible upswing in the economy of Japan.
That combination, could, in the short term, cause the yield spread to shrink.