The OECD stats look quite interesting. They break things down into Type A[1] and Type B[2] programs. Superficially, Type A are 3+ year courses, Type B are 2+ year courses. Results for the UK and US are here[3][xls]. Executive summary: for the 3-4 year Type A graduates, in the UK, 97% graduate. The OECD average is 67%. This report also has data for the US.
For actual numbers of people in the UK with degrees, there's this page[4] from the National Statistics. For people of Working Age, 18 to 60-ish, in the UK, 16% have degrees, and another 8.5% have "Higher education qualifications". 15% have no qualifications. It would be handy to have data for the 25-35 age range, since not many 18 year olds have degrees.
For actual numbers of people in the UK with degrees, there's this page[4] from the National Statistics. For people of Working Age, 18 to 60-ish, in the UK, 16% have degrees, and another 8.5% have "Higher education qualifications". 15% have no qualifications. It would be handy to have data for the 25-35 age range, since not many 18 year olds have degrees.
[1] Type A: http://stats.oecd.org/glossary/detail.asp?ID=5440
[2] Type B: http://stats.oecd.org/glossary/detail.asp?ID=544
[3] World Stats: http://www.oecd.org/dataoecd/17/15/39245059.xls
[4] UK Degree Stats: http://www.statistics.gov.uk/STATBASE/Product.asp?vlnk=10446