In this study, the presenter used three research questions to investigate how learners incrementally increase their TOEIC test scores through extensive reading. The first question concerns the number of English words that must be read to reach the intermediate level. MReader and the TOEIC online test scores were used to estimate the words that is necessary to reach the CEFR B1. As a result, it was estimated that reading about 500,000 words was required. The second question is about identifying which factors most affect the final TOEIC scores. What had a greater effect on the TOEIC scores, the learner's initial academic ability or their reading volume? This looks like the classic chicken and egg problem, but multiple regression analysis of the data showed that the amount of reading affected their test scores more than their initial ability. The third question is about the students’ motivation. What psychological factors affect the amount of reading? The presenter used multiple regression analysis and found that the students’ positive attitudes toward reading were influencing the total amount of reading being done. The details of the classroom setting and analysis will be shared during the presentation.