This question came up because we've been playing about with the default assumptions used in the Student Finance calculator on the Money Saving Expert website. They assume average salary growth of 2% a year, so we wanted to see how that compared with our own salary growth.
There are lots of compound interest calculators online, but we used this one (ignoring the fact that its in dollars): www.calculatorsoup.com/calculators/financial/compound-interest-calculator.php.
Both of us graduated and started work in 1993 in London - DH on £11k in the Civil Service and me on £13k at a University. Since then we've both changed jobs a few times and developed careers in analytical areas. We're not super-ambitious types - just slow and steady, easy going, stress-averse. I have had 2 year-long career breaks and worked part time since our first son was born in 2004, and have remained as a senior analyst (still at a university) rather than seeking a higher stress management position, whereas DH is now a director of a small department at a FTSE 100 company. Using the compound interest calculator, we worked out that DH's base salary has increased by an average of 8.6% per year (not including his annual bonus), whereas mine has increased by 5.1% per year.
I was prepared for DH's salary to be much higher than the assumed 2%, but I was surprised that mine was so much higher. It makes me wonder how valid the assumptions are in the MSE calculator - I'm not sure they take into account the fact that graduates often move jobs in order to increase their salary and status, or get promoted, rather than sitting in the same job getting small inflationary rises each year.