In the late 1980s Batia Laufer worked with teachers who believed that to understand a text it was enough to understand 80% of the text's word tokens. In response, Laufer set out to calculate the minimal text coverage, i.e., percentage of running words in a text the reader should understand to comprehend it reasonably well. In 1992, she explored…

We explore the relationship between second language (L2) learners' vocabulary size, lexical text coverage that their vocabulary provides and their reading comprehension. We also conceptualize "adequate reading comprehension" and look for the lexical threshold for such reading in terms of coverage and vocabulary size. Vocabulary size was…