The research is based on Office for National Statistics (ONS) figures analysed by age and sector.
It reveals the average salary for senior managers and directors between 40- and 49-years-old is £67,232. For employees at a similar level aged 50- and 59-years-old, it drops down to £63,565.
Average earning power only rises after 50 in three sectors – teaching, healthcare and secretarial. For all three areas salaries are the highest for employees over 60-years-old.
Healthcare professionals 60 or older earn on average £50,418, compared to £44,298 in their 40s.
The average salary across all sectors peak at £33,459 between 40 and 49. This drops off to £33,059 at 50 and £31,059 at 60.
Close Brothers Asset Management director of financial education Jeanette Makings told HR magazine older employees displaced during the financial crash may have elected to take partial retirement or coaching roles.
"If there were voluntary redundancies available, those who could afford to sometimes took the opportunity to look at alternative options to continuing the traditional career path," she said. "From maybe shifting to working part-time to taking a less stressful job in another sector, there are plenty of reasons why their earning power may have decreased."
Makings added there are sectors that value older workers more than others.
"In something like teaching or engineering, grey hair is actually seen as an asset. Experience is key in fields like that," she said.
