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Excel: the number data type

The Excel data type number is used to store numbers (which seems obviously) and also dates (see serial numbers).
The representation of a number is controlled by a Range's numberFormat property or the Number tab in the Format Cells dialog box (to be opened with right-click on a cell/range or via Ribbon-Home -> Number)

TODO

Apparently, Excel considers a number stored as text to be an error.

See also

The worksheet function type(value) returns 1 for number values.
Excel data types

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