Am I completely mis-reading the report? By following the same people, the report grossly states that someone's salary tend to go up with age. How revolutionary!

Am I completely mis-reading the report? By following the same people, the report grossly states that someone's salary tend to go up with age. How revolutionary! I'm pretty sure the vast majority of people draw better salaries with teh more experienced they get. This has nothing to do with the repartition of the increase of the economy.