Michael West was one proponent for focusing more on vocabulary due to his experience teaching Indian students to improve their reading proficiency. In this time, he was involved in a study noting the frequency of words across texts. This led to the publication of the Interim Report on Vocabulary Selection for the Teaching of English as a Foreign Language in 1936 and the revised 1953 a General Service List of English Words.
According to West (1954), some 2.5 to 5 million words were counted in preparing these lists. Considering that such a task would now be accomplished in seconds by a corpus, it may be difficult for some to imagine the time this would have taken back in the 1950s! The goal was to aid teachers in defining a minimum adequate vocabulary their students would need. Interestingly, West (ibid) notes that this minimum adequate vocabulary may depend upon the students’ circumstances and therefore the general service list should be viewed as no more than a guide.