Wages grow with age, but there is a point of diminishing return where retirement may be a better alternative to continuing to work with scant hope for increasingly higher pay. In Idaho for example, cost of living adjustments yielded greater increases for retirees than state workers experienced on their paychecks during the Great Recession.
This depends on the industry, however. There are a number with older leadership and workforce such as utilities, education and agriculture. The mid-life years of 45 to 54 are the peak wage-earning time.