There is an NTID center that gathers information on this topic, Collaboratory on Economic, Demographic, and Policy Studies. Information here is from their website. More than 50 percent of D/HH persons have attained only a high school or less than high school education compared to only 40 percent for hearing persons. Twenty-four percent of those who are D/HH are college graduates compared with 39 percent for the hearing population. Check out this report.
Walter, G., (2010). DHH students in transition: Demographics with an emphasis on STEM education. Rochester, NY: National Technical Institute for the Deaf, Rochester Institute of Technology.
Cuculick, J. A., & Kelly, R. R. (2003). Relating deaf students’ reading and language scores at college entry to their degree completion rates. American Annals of the Deaf. 148(4), 279-286.
According to the 2010-2012 ACS which was adjusted to reflect an approximation to the population narrowed to those aged 26-64 (free of age-related deafness, ie, loss of hearing in old age), Richard Dirmyer, an NTID researcher, rcdnvd@ntid.rit.edu shared this information.