A 1999 survey of patients who had rheumatoid arthritis, osteoarthritis, or fibromyalgia and were seen by rheumatologists reported that 18 percent had used magnets or copper bracelets, and that this was the second-most-used CAM therapy by these patients, after chiropractic. One estimate places Americans' spending on magnets to treat pain at $500 million per year; the worldwide estimate is $5 billion.⁷ Many people purchase magnets in stores or over the Internet to use on their own without consulting a health care provider.