Recently, attention has turned to the Bank of Japan’s actions to defend the yen exchange rate, and the scale of this intervention really is not small. According to analysis, Japan may have injected about $34.5 billion to support the yen on Thursday—its first move since July last year—amounting to roughly 5.4 trillion yen. Compared with the four interventions last year, which averaged about 3.8 trillion yen each, this time is clearly more aggressive.

What’s interesting is that Finance Minister Mayu Katayama had hinted in advance that “decisive action” was on the way, and as a result, the yen appreciated sharply on Thursday evening. Later, insiders confirmed that the authorities had indeed entered the market to carry out the operation. The central bank’s data released on Friday makes the point even clearer: the current account is expected to decrease by 9.48 trillion yen, far exceeding market expectations of a 4.08 trillion yen decline, which shows the authorities’ determination to intervene.

I think the effect of this yen rally is quite noticeable. In the short term, the yen has appreciated by more than 3%, and the market generally believes the initial results are good. But Mayu Katayama’s warning is also quite interesting—she told traders to stay vigilant and even not to put down their phones during Golden Week, implying that there may be further actions to come.

From the market’s perspective, Japanese authorities’ stance toward the yen exchange rate is very firm. This is not just a short-term defensive battle—it’s more like a signal that they will continue to monitor and intervene. For traders who are watching moves in the yen exchange rate, this period really calls for extra attention to changes in policy; after Golden Week, there may be more to look at.