The earlier jump in USD/JPY above 131.20 was in a time of low liquidity :
Asia is up and running fully now, and its dropped back much lower for the session:
No fresh news nor data apart from what has been posted.
USD/JPY starting out 2023 with more of the swings seen in December 2022!
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I thought the significant news out of Japan over the break was this from Saturday:
If you are looking for news to drive the yen up this'd be a candidate.