Enter the base value in a blank cell which you'll use to increase the value of existing cells. As an example, to add 10 to each cell, enter "10" (without the quotation marks here and throughout).

Excel's spin button lets you quickly increase or decrease a value in a cell without having to type it manually. It can be used in wide-ranging contexts, such as a data entry form, a dashboard ...

Excel has a surprising limitation that you may not discover until you try to enter more than 15 digits in a cell. The application can only store numbers with15 digits of precision.