"Lost productive time varied to some degree in the workforce. First, little or no variation was observed by age. In large part, the lack of differences by age was due to the counterbalancing effects of different pain conditions. Headache, common at younger ages (ie, 18-34 years), rapidly declines in prevalence thereafter. In contrast, the other 3 pain conditions are either more common with increasing age (eg, arthritis) or peak at a later age than headache (eg, back pain)."
Stewart WF, Ricci JA, Chee E, Morganstein D, Lipton R. Lost Productive Time and Cost Due to Common Pain Conditions in the US Workforce. JAMA. 2003;290(18):2443–2454. doi:10.1001/jama.290.18.2443