The yen headed for its biggest weekly loss in three months on Friday as the impact of U.S. and Japanese intervention faded, leaving traders to wager another round of official buying would be needed to stem the rot.
The currency has surrendered roughly half the gains sparked by intervention in late July and early August, falling about 1% this week to 159.43 per dollar. It was trading near 164 per dollar before July's intervention and traders see the 160 level as a potential trigger for fresh official action.
