"A total of 52.7% of the workforce reported having headache, back pain, arthritis, or other musculoskeletal pain in the past 2 weeks. Overall, 12.7% of the workforce lost productive time in a 2-week period due to a common pain condition; 7.2% lost 2 h/wk or more of work. Headache was the most common pain condition resulting in lost productive time, affecting 5.4% (2.7% with >= 2/wk) of the workforce (Table 1), which was followed by back pain (3.2%), arthritis (2.0%), and other musculoskeletal pain (2.0%)."

Source

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