New Year's Eve is December 31 on Japan Exchange Group (JPX) calendars. It covers Tokyo Stock Exchange (TSE) cash equities, Osaka Exchange (OSE) and Tokyo Commodity Exchange (TOCOM) derivatives, Bank of Japan offices and administrative organs. It is a standing non-business day for TSE cash equities, with no auction sessions all day. It stays excluded from OSE and TOCOM holiday trading.
It is an annual observance every December 31 and signals open or closed status. It measures no activity, sentiment, prices or volume, and it is not a national holiday.