ConstReadonlyBelowTable: "belowTable"The formula stays below the table, which does not grow.
ReadonlyInsideTable: "insideTable"The row becomes a row of the table, as a value would.
ReadonlyTotalsRow: "totalsRow"The row becomes the table's totals row, and the formula its column's total. The other columns total nothing, unless the table held totals from a totals row shown earlier. The default.
Where a formula entered in the row just below a table goes, when the table has no totals row showing and grows down (see ITable.AutoExpand).