UsageSummary resource costAdditionalDetailLastPeriod monetary entries should NOT include a measurement entry because the ESPI standard defines billLastPeriod as an Int48 that represents the data in hundred-thousandths of the currency specified in the ReadingType for this reading. Therefore, it is unnecessary to provide a measurement as long as the entry is in hundred-thousandths. However, implementations have surfaced that include a measurement entry with a uom of 80 (currency) but do not use hundred-thousandths or a correct powerOfTenMultiplier for monetary values.