This paper reports the changes in English proficiency measured by TOEIC scores during the two-year liberal arts education period for university students enrolled between 2013 and 2017. This is not simply a comparison between the time of admission and the end of the second year, but an analysis of the changes in English proficiency over two years based on a close look at the results of five TOEIC tests administered towards the end of each semester. The analysis revealed that while the English proficiency of students generally improved at the end of the second year, they didn't necessarily achieve their peak scores during the final semester of the second year and that their score range, or the difference in English proficiency among students, widened over time. According to the analysis by semester, there were ups and downs in their scores over two years, but all in all, the performance in the first semester of the first year was excellent, and it tended to slow down in the second year.