The proportion of students in England awarded first-class degrees has fallen for the first time in over a decade, the university watchdog says.
The Office for Students (OfS) says 32.8% achieved top grades in 2021-22, down from 37.4% in 2020-21.
But the percentage remains higher than before the Covid pandemic and concerns remain about the overall increase since 2010-11, when it was 15.5%.
Universities say they are "committed to addressing unexplained increases". The National Union of Students (NUS) said it "regrets" students were having "doubts cast upon their achievements".
Universities UK, which represents 140 institutions, said they were "rowing back on increases that occurred during the pandemic".
In a statement, it referred to guidance it has published on how universities should classify degrees to "protect the value of qualifications".
The fall in the proportion of top grades in 2021-22 coincided with many universities ending "no detriment" or "safety net" policies designed to protect grades from being negatively impacted by disruption during the pandemic.
The policies often meant students' grades were based on their performance up until the pandemic. The OfS report does not analyse the impact of policies and guidance.
