Выражение встречается в следующем контексте:
Interest shall be payable, for each week or part thereof during which the payment delay lasts, at an annual rate of interest which by eight percentage units exceeds the one week STIBOR rate (Stockholm Interbank Offered Rate), which is fixed two banking days before the first day of each such period. However, in respect of no day, shall interest be payable at a rate below the reference interest rate fixed by the Bank according to the Act on Interest Rates prevailing at any one time plus eight percentage units.

Заранее спасибо