Show AllMatch all open and close parentheses Make sure all parentheses are part of a matching pair. When you create a formula, Microsoft Excel displays parentheses in color as they are entered.
Use a colon to indicate a range When you refer to a range of cells, use a colon (:) to separate the reference to the first cell in the range and the reference to the last cell in the range.
Enter all required arguments Some functions have required arguments. Also, make sure you have not entered too many arguments.
Nest no more than seven functions You can enter, or nest, no more than seven levels of functions within a function.
Enclose other sheet names in single quotation marks If the formula refers to values or cells on other worksheets or workbooks and the name of the other workbook or worksheet contains a nonalphabetical character, you must enclose its name within single quotation marks ( ' ).
Include the path to external workbooks Make sure each link contains a workbook name and the path to the workbook.
Enter numbers without formatting Do not format numbers as you enter them in formulas. For example, even if the value you want to enter is $1,000, enter 1000 in the formula.