The paste special feature is useful for preserving the values in a spreadsheet – but removing the formulae that generated those values. This may be required to preserve proprietary equations.
To remove the formulae for a range of cells, select and copy the desired range. Do not unselect the range. Now click on Edit – Paste Special – see below.
Make sure the Formulas box is unchecked. After you click OK, the formula is removed but the value is preserved.