Grid, Board & Gallery — Totals at the foot of a column (2)

Computed columns total too. A rollup always totals as a number; a formula totals as the kind of value it produces — a number, a checkbox or text; and a lookup totals as the field it shows, when its link reaches a single record. The one that can't is a lookup across a link to several records, whose cell is a list rather than a value, and a formula RowFold can't work out in the database offers no total rather than a wrong one. A summary with no answer shows — rather than 0, because 0 is a claim about your data. Group totals sit in the group's own header, so they stay readable collapsed — which is when a total is most useful.