Formula Errors

• Excel formulas need to contain correct syntax. Each formula must start with an "=" or a "+." These symbols tell Excel that the cell contains a formula. Verify that the formula contains the appropriate number of parenthesis. For every opening parenthesis there must be a closing parenthesis. Make sure that your formula contains a colon instead of a semi-colon to represent a range of cells. If using a function, verify that all of the required arguments are set.
  
  

Formatting Errors

• Another cause for formulas not calculating is the cell that contains the formula is formatted incorrectly. The data type of the cell controls how the information is displayed. For example, a cell that has the Text data type will not calculate formulas. The cell needs to use the General or Number data type to calculate formulas. Set the cell format by selecting "General" or "Number" from the drop-down menu in the "Number" group on the "Home" tab.
  
  

Circular References

• Circular references are another common reason for formulas not calculating. A circular reference means that the cell that contains the formula is referenced in the formula. Excel displays a circular reference warning message; however, if this warning has been turned- off, the formula result will be a zero.
  
  

View Formulas

• The easiest way to find errors in your spreadsheet is to view all formulas instead of viewing all formula results. To accomplish this, press "CTRL" and then the "`" key, located above the "Tab" key on your keyboard. You may need to resize your columns to see the complete formula. To view the formula results, press "CTRL" and then "`" again.