ClickHelp Documentation

Unique Text Metric

The Unique Text metric displays the number of unique words in a topic and their percentage as compared to words shared with other topics. The metric calculation approach is simple: unique text is all topic text except for variables and snippets. Headers and footers defined in the Topic Master Page settings do not affect the calculation.

So, the number of words you see in this metric refers to all words which are not reused through Variables and Snippets.