Major depressive episode

If left untreated, a typical major depressive episode may last for about six months. About 20% of these episodes can last two years or more. About half of depressive episodes end spontaneously. However, even after the major depressive episode is over, 20% to 30% of patients have residual symptoms, which can be distressing and associated with disability.

Question: can a major depressive episode last for years
Answer: yes