CENTER FOR EDUCATION STATISTICS
OFFICE OF EDUCATIONAL RESEARCH AND IMPROVEMENT 
U.S. DEPARTMENT OF EDUCATION


                                   
SUBJECT:   STANDARD FOR ROUNDING
EFFECTIVE DATE: 02/09/87   CES STANDARD 87-03-06
                                   
PURPOSE: To assist researchers in attempting to summarize and study the data from a survey.    
                                   
  o Before rounding figures for publication, decision must be made about the appropriate number of significant digits. The problem of implying a spurious degree of accuracy must be balanced with the need to have consistency between and within tables.
                                   
  o When adding, multiplying or dividing figures that have been rounded to different significant digits, the product can only be stated in terms of the number with the fewest significant digits. (If 4.5 and 5.75 are rounded numbers, the product can be stated only as 26, with 4.5 having two significant digits and 5.75 having three.)
                                   
  o Tabulations to produce summary data and computations-performed for purposes of estimating standard errors should be done on unrounded numbers.          
                                   
  o Sums of column (row) figures in a table should be derived using unrounded figures, with appropriate rounding of the total after its derivation. To handle the problem of column (row) figures not summing to
    a rounded total, an explanatory footnote should be used.            
                                   
  o The final rounded value should be obtained from the original figure available, not from a series of roundings (e.g. 7.1748 can be 7.175 or 7.17 or 7.2 or 7 but not 7.18).    
                                   
  o Percentages should generally be rounded to no more than one decimal place.        
                                   
  o Specific rules to be used for rounding:              
                                   
      If the first digit to be dropped is less than 5, the last retained digit is not changed.      
                                   
          6.1243 6.124                    
                                   
      If the first digit to be dropped is greater than or equal to 5, the last digit retained is increased by 1.    
                                   
          6.688 6.69                      
                                   
  o Documents need footnotes explaining cases where actual numbers are used in all calculations, and rounded results are presented which seem inconsistent.  
                                   
RELATED STANDARDS:                            
                                   
RELATED CHECKLISTS, FORMS AND DOCUMENTS:                  
                                   
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