Record levels of top honours students recorded as 24% gain first in 2016
The proportion of students leaving university with top honours has reached record levels in the last five years, figures show.
Almost one in four (24%) graduated with a first last year, compared with 17% - just over one in six - in 2011/12, according to data published by the Higher Education Statistics Agency (HESA).
The figures, which cover UK universities and colleges, are likely to spark fresh debate about whether the centuries-old degree classification system is still fit for purpose.
In recent years, a number of employers have stopped asking for specific degree standards, with one expert saying that firms do not want to miss out on highly qualified candidates simply because they did not gain a certain degree.
Overall, in 2015/16, almost three in four students - 73% - were awarded at least an upper second (2:1), compared with 66% just five years earlier.
A breakdown also shows a slight drop in the proportion of students awarded lower honours, with just over a fifth of students (22%) gaining a lower second (2:2) in 2015/16, and 5% graduating with a third.
Graduate recruitment expert Martin Birchall, of High Fliers Research, said some employers are no longer using a "blunt cut-off" of degree classification, a move that comes amid the rise in graduates gaining high honours.
"In recent years, diversity has become a real issue for many employers and they're keen to have as broad a spread of applicants for their graduate programmes as possible," he said.
"That means they don't necessarily want to cut out graduates who did not get a first or a 2:1 but have CVs that are jam-packed with other skills and experiences that may be more relevant in the workplace.
"A number of employers have realised that if they use a blunt cut-off such as a 2:1 or above, they're missing out on some great people, so degree classification has become less important."
"It's very hard to understand why more and more students are getting these top grades.
"Degrees are not benchmarked as a national standard, so there is no way of telling whether individual universities are becoming more generous in the degrees they are awarding or whether standards are genuinely rising."
Mr Birchall said the bottom line for employers is that they are now looking for much more than academic qualifications in job candidates.
But he added: "It makes life harder if almost everyone who applies for a graduate job comes with a first or a 2:1 because employers can't use that to differentiate between candidates."
In 2015, professional services firm Ernst and Young announced it was to remove academic and education details, including degree classifications, from its trainee application process and would decide who to interview based on candidates' performance in online tests.
And publishing firm Penguin Random House UK has announced that it is scrapping the requirement for future workers to have a university degree.
It said there is increasing evidence that there is no simple link between having a degree and performance in the workplace.
The figures show that UK students made up 81% of enrolments at UK universities and colleges last year.
The overall number of EU students rose by 2% on 2014/15 to make up 6% of enrolments, while students from outside the EU made up 14%.
While some countries are sending increasing numbers to study in the UK, the numbers are falling in other nations.
Among countries outside the EU, in 2015/16, the number of student enrolments from China was 12,500 more than in 2011/12.
India saw the largest percentage decrease in students, dropping 44% over the five-year period.
The statistics also show that the numbers of people choosing to study part-time continues to drop.
The Sutton Trust charity said it was concerned at a 47% fall in recent years in part-time students.
Chief executive Dr Lee Elliot Major said: "While it is good to see that more and more people are starting higher education, it is seriously concerning that there's been another dramatic fall in the number of people choosing to study for degrees part-time.
"Studying part-time has traditionally offered a second chance for people from less advantaged backgrounds who missed out on university after school. Since tuition fees were introduced, their numbers have almost halved.
"This is likely having a serious and detrimental impact on social mobility."
Nick Hillman, director of the Higher Education Policy Institute (Hepi), said: "The situation does need monitoring very closely. There are valid questions about whether growing competition between universities is encouraging grade inflation and also whether the external examiner system is fit for purpose in every respect.
"After all, it is in no-one's interests - not government, employers or universities - for people to think students are having an easier ride than in the past.
"But it would still be wrong to see the figures as proof of a crisis because the controversial £9,000 tuition fees mean facilities have got better, while students seem to be drinking less and working more."