Array formulas are similar to regular formula in that they have the same grammar. However, array formulas must be set on a single region of cells only. When the array formula is applied to a region of cells, each cell's Formula property will be the array formula. The Value of each cell cannot be changed unless ClearCellRange is called on the array formula or another value is applied to a region of cells which completely contains the array formula's region.

Because the array formula stores the region of the cells to which it is applied in the CellRange property, the array formula can only be applied to one region of cells.

Array formulas are created through Microsoft Excel by selecting a region of cells, entering a formula for that range, and pressing Ctrl+Shift+Enter. This causes the formula of each cell in the region to appear as follows: {=Formula}.

See the Microsoft Excel documentation for more information on array formulas.

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