Explanation of Grammar Checker Readability Statistics

• Microsoft Word for Windows, versions 2.0, 2.0a, 2.0a-CD and 2.0b
• Microsoft Word for the Macintosh versions 5.0 and 5.1

SUMMARY

Readability statistics measure how effectively a piece of writing communicates its meaning to the reader. The Microsoft Word Grammar command can generate this type of statistics.

The readability formulas for the document statistics and comparison charts are the Gunning Fog Index, Flesch-Kincaid, and Flesch Reading Ease. These three formulas are discussed below. For more information on readability formulas, refer to "Grammatik User's Guide," "Microsoft Word for Windows User's Guide," or a technical writing textbook.

MORE INFORMATION

Equation Legend

"x" Denotes multiplication "+" Denotes plus or addition "-" Denotes minus or subtraction

Gunning Fog Index

This index combines sentence length and the number of multisyllable words per sentence to give a readability rating. Higher scores indicate more difficult text.

   Total= (Average number of words per sentence) + (Number of words of
          three syllables or more)

   Fog Index= Total x (0.4)

Flesch-Kincaid

This index indicates the grade level of a reader who would be most comfortable reading the document. Sixth to tenth grade level is considered the normal range at which most documents should read. Levels higher than that should be targeted to a particular audience.

   Total= (0.39) x (Average number of words per sentence) + (11.8) x
          (Average number of syllables per word)

   Grade Level= Total-(15.59)

Flesch Reading Ease

This index provides a score ranging from 0-100 that is based on sentence length and the number of syllables per 100 words. This score corresponds to the Flesch Grade Level index below.

   Total= (1.015) x (Average sentence length) + (0.846) x (Number of
          syllables per 100 words)

   Flesch Reading Ease Score = (206.835)-Total

Score   Reading Difficulty    Grade Level
-----   ------------------    -----------

100-90  Very easy             4th
90-80   Easy                  5th
80-70   Fairly easy           6th
70-60   Standard              7th-8th
60-50   Fairly difficult      Some High School
50-30   Difficult             High School Plus
30-0    Very difficult        College Plus

"Microsoft Word for Windows User's Guide," version 2.0, pages 290-291

"Grammatik IV User's Guide," Chapter 7

"Communications in Business and Industry," William Schutte & Erwin Steinberg