The sources that matter

The Bank of Japan publishes monetary-policy meeting schedules, summaries and minutes; the Fed maintains its decision calendar. Use those primary documents to distinguish what central banks said from commentary about what they might do.

Why yield spreads are not a mechanical forecast

Interest-rate differentials, hedge costs, positioning and global risk demand can all affect yen transactions. A spread between two government-bond yields is not an executable currency return and cannot reliably predict the next USD/JPY price by itself.

Research trail

Begin with USD/JPY and yields and margin risk. Record the currency, time zone, trading venue and applicable broker costs when evaluating a historical currency event.