B.1.5.EW:5.2 - An update within a running calculation

An analyst is totaling accepted observations as part of preparing a report. The algorithm maintains a running sum. On reading the next value, adding it to the accumulator is a constituent of computing the total; computing that total is part of the report preparation currently under way. The addition, computation and report preparation do not incur three copies of that minute of work.

The addition is correct over the supplied numbers. The report, however, requires excluding duplicate observations. If duplicate detection is missing, more precise addition cannot repair the report. Recover the accepted-observation rule and apply it before the affected update. The genuine order remains: the next update consumes the current accumulator, and the report cannot use the final total before the calculation finishes.

A scheduler running on the same machine overlaps the calculation. That overlap alone makes it neither an arithmetic constituent nor report-preparation Work.