"The OECD measures
education outcomes based on the educational attainment, skills and years in education. OECD’s member countries include Sweden, France, Turkey, South Korea and Colombia. Its data included 37 to 41 countries, depending on when it was collected and which countries participated.
The U.S. ranks eighth out of 41 countries in the portion of people with at least a secondary, or high school, education, with 92% of its people aged 25 to 65 holding a diploma"
That isn't just making up a number and continuing to repeat the lie until his mass of lemmings believe it's true.