How Common Are Mood Disorders?
About 20% of the U.S. population reports at least one depressive symptom in a given month, and 12% report two or more in a year. A survey conducted in 1992 found rates of major depression reaching 5% in the previous 30 days, 17% for a lifetime. Bipolar disorder is less common, occurring at a rate of 1% in the general population, but some believe the diagnosis is often overlooked because manic elation is too rarely reported as an illness.
