Of course it was based on the number of dollars, but based on which figures? It was an assertion conjured out of thin air. If there are five times as many undergrad students as grad students and a similar percentage of grad students had to take out student loans, then this would mean that students are incurring on average five times more debt for graduate school. This is without taking into consideration that a far higher percentage of US graduate students are international students.
It looks like graduate debt was approaching the majority and could in fact be a majority in 2024: "If these trends continue, graduate loan disbursements may exceed undergraduate disbursements in the next few years." https://sites.ed.gov/ous/files/2023/08/OCE_GraduateDebtRepor...
You're conflating current disbursements with the outstanding debt, which is what the original assertion was on. Either way it is looked at though, their assertion is wrong.
> You're conflating current disbursements with the outstanding debt
No, I was just googling for stats, and that's what I was able to find. Here's something else though: "46% of federal student loan debt belonged to graduate student borrowers in 2017." https://educationdata.org/average-graduate-student-loan-debt