There is something very funky about the numbers used in this article. All their charts are measuring "enrollment gap", defined as (percentage of college-age pop

There is something very funky about the numbers used in this article. All their charts are measuring "enrollment gap", defined as (percentage of college-age population) minus (percentage enrollment). But this conflates changes in enrollment with changes in population. This is especially obvious when looking at the graph for Hispanics, where the number of college-age Hispanics has greatly increased from 1980 to 2015; the "gap" has grown from 3% to 9%, but without using a ruler, it's hard to tell whether the actual percentage of Hispanics attending college has gone up or down! This makes me feel like the author of the article is trying to deceive me, and I'd much rather get numbers from somewhere else.