Over the period of 2009 to 2011, an estimated 102.5 million persons annually reported a musculoskeletal disease in the Medical Expenditures Panel Survey (MEPS). The annual average proportion of the United States population with a musculoskeletal disease has increased by more than five percentage points between 1996 to 1998 and 2009 to 2011, from 28.0% to 33.2%. Musculoskeletal disease now includes about one-third of the population. The growth in the number of cases of musculoskeletal disease is more a function of the number of persons in the ages of increased incidence than in overall increase in all age groups. (Reference Table 10.1 PDF CSV)