The sheet calculations are probably set to manual. You can press F9 to do it manually or turn in automatic calculations.
To turn on automatic do the following:
Click the File tab, click Options, and then click the Formulas category.
Do one of the following:
- To recalculate all dependent formulas every time you make a
change to a value, formula, or name, in the Calculation options
section, under Workbook Calculation, click Automatic. This is the
default calculation setting.
- To recalculate all dependent formulas — except data tables — every
time you make a change to a value, formula, or name, in the
Calculation options section, under Workbook calculation, click
Automatic except for data tables.
- To turn off automatic recalculation and recalculate open
workbooks only when you explicitly do so (by pressing F9), in the
Calculation options section, under Workbook Calculation, click
Manual.
Note: When you click Manual, Excel automatically selects the Recalculate workbook before saving check box. If saving a workbook takes a long time, clearing the Recalculate workbook before saving check box may improve the save time.
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