National Health and Nutrition Survey (NHANES) is sponsored by the US. government. Researchers use data from NHANES extensively in studies related to health of the US. population. According the NHAN ES website, "The survey is unique in that it combines interviews and physical examinations. ...The survey examines a nationally representative sample of about 5,000 persons each year." Do younger U.S. males weigh more on average than older males? Here are summary statistics relevant to our research question. Sample Mean Standard size weight (kg) deviation (kg) 20-29 years old 75+ years old