Unrecognized and untreated depression is currently the most common serious public health problem in college students. The impact of depression is substantial, including reduced student retention, learning and success. The National College Health Assessment, the American College Health Association's annual student survey, reported that the percentage of college students who reported receiving a diagnosis of clinical depression increased from 10% in 2000 to 16% in 2005. In a population of nearly 18 million students, as many as 2.35 million college students may experience significant depression during their college years. Of the 94,806 students who participated in the 2006 National College Health Assessment, 52.4% reported "Feeling things were hopeless" 1-10 times during the past school year; 36.7% were "Feeling so depressed it was difficult to function" 1-10 times; and 9.3% found themselves "Seriously considering attempting suicide.