Applying Conditional Formatting
You can make your reports and forms more powerful by setting up conditional formatting. Conditional formatting allows you to format a field based on values the user enters. For example, you can use a conditional format to make negative values appear in red and positive values appear in black. 
 Apply Conditional Formatting to a Field
  |  Display the form or report in Design view, and then click the field to which you want to apply conditional formatting.  |  
   |  Click the Format menu, and then click Conditional Formatting.  |  
   |  Specify the default format for the field.  |  
   |  Click the Condition 1 list arrow, and then select Field Value Is.  |  
   |  Click the second list arrow, and then select a condition type.  |  
   |  Enter values for the condition.  |  
   |  Specify the format when this condition is true.  |  
   |  Click Add to add a second formatting condition.  |  
   |  Click OK to apply the conditional formatting.  |   
 
  
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 You can use expressions in a conditional format. 
For more complicated conditional formats, select the input field, click the Format menu, and then click Conditional Formatting. Click the Condition 1 list arrow, select Expression Is, type the conditional formatting expression in the box to the right, and then click OK.  |  
  
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