The phrase "disproportionate rates" means that something is happening or occurring at significantly different or uneven proportions or quantities. Full definition
Yet while numerous studies described the problem of disproportionate rates of suspensions, only a handful examined potential solutions. (educationnorthwest.org)
According to the waiver request, different groups of students opt out of testing at disproportionate rates. (deseretnews.com)
The study also found that even accounting for crime patterns in the city's various neighborhoods, officers stopped minorities at disproportionate rates. (lawyerist.com)