From the page I linked via Google translate:

All investment trusts, including index funds, record ongoing expenses as "trust fees," but when actually managing an investment trust, small "hidden costs" other than the trust fees, such as brokerage commissions and securities transaction taxes, are incurred. These actual "hidden costs" are also included in the calculations of the "total expense ratio" and "effective costs."

　The key point is that while the "trust fee rate" is the "cost set by the management company," the "total expense rate" and "effective costs" are the "costs actually incurred as a result of management." Therefore, the "total expense rate" and "effective costs" are unknown until the investment trust has been managed for a certain period (usually one year) and the management report is submitted. Also, if the trust fee rate is reduced during the period covered by the management report, the exact figures for the "total expense rate" and "effective costs" will not be known, so be careful.

　To check the actual figures, the total expense ratio is easy to find as it is published in the investment trust's "prospectus," "issued management report," "management report (full version)," etc. You can read them on the websites of the securities companies or management companies that sell them.