The age doesnt necessarily indicate how long it took to get there. The age of grad entrants can vary dramatically according to the extent of their education (masters, phd), whether they took Gap Years, the country they studied in and whether they had to do social or military national service - in my start group we had people who were 21, 22, 23, 24, 25, a couple in their late 20s and a couple in their early 30's.Given the financial crises over the past decade, the time to promotion at a lot of firms has increased as well, so i dont know about now but if you had joined a uk firm in the late 90's/early 00's then with ACN as an example, from grad you'd probably be C1 at 12-18 months, M1 at 4.5 - 5 years, (and assuming the stars were aligned) SM at 7.5 - 8 years.