Challenge 2: Refreshing After Adding New Source Rows — Solution Walkthrough

What needs to happen:

Right-click anywhere inside the Pivot Table and choose Refresh (or
Data > Refresh Range/Pivot Table). Without this explicit step, the
Pivot Table continues showing its old totals, completely unaware
that 10 new rows now exist in the source data — it does not update
itself automatically just because the underlying data changed.

Why this isn't a LibreOffice-specific quirk:

This exact manual-refresh requirement is identical in Excel — Excel
Fundamentals Chapter 9 established that a PivotTable is a cached
SNAPSHOT of its source data at the moment it was last built or
refreshed, not a live, continuously-recalculating view. Both
applications treat a Pivot/PivotTable the same way for the same
underlying reason: recalculating the full summary automatically on
every single source-data edit would be expensive to do continuously,
so both defer that recalculation until explicitly requested via a
refresh action.

WHY THIS WORKS AS AN ANSWER
------------------------------
This is one of the few genuinely IDENTICAL behaviours this chapter
calls out explicitly rather than a difference — worth confirming
directly, since after several chapters of genuine differences (Page
Styles, the Mail Merge Wizard, the Layout dialog itself), it's
tempting to assume everything about Calc's Pivot Table differs from
Excel's. The refresh requirement specifically does not.