The level of financial inequality among U.S. higher education institutions has important implications for students and society, yet few scholars have examined this topic using established methods for measuring inequality. This paper updates and extends previous work while introducing decompositions that shed light into key trends that we observed for the 2004–2017 period: increasing inequality in total expenditures and decreasing inequality in per-student expenditures. The results of our decomposition highlight how these opposing trends related to rising differences in enrollments and an increasingly positive correlation between an institution's enrollment level and its expenditures per student. Our decomposition results also show that both between-group differences and within-group differences contributed to the observed trends. Further examination of within-group differences reveals that inequality patterns differed meaningfully by institutional type, with doctoral universities and private baccalaureate colleges possessing higher levels of inequality and a more positive correlation between per-student expenditures and enrollments than master's institutions and public associate's colleges.

美国高等教育机构之间的财务不平等程度对学生和社会具有重要意义，但很少有学者使用已建立的衡量不平等的方法来研究这一主题。本文对先前的工作进行了更新和扩展，同时引入了分解，揭示了我们在2004-2017年期间观察到的主要趋势：总支出中的不平等增加和每学生支出中的不平等减少。我们分解的结果凸显了这些相反的趋势如何与入学率差异的不断增加以及机构的入学率及其每名学生的支出之间的正相关关系日益增加。我们的分解结果还显示，组间差异和组内差异均对观察到的趋势有所贡献。