January effect
n.— «Fundis in behavioral finance have put forward a number of reasons why the first month on the Christian calendar year is invariably bountiful in terms of stock market returns. In the United States, they use the term “January Effect” to describe this phenomenon.» —“The Rich Pickings of a Special Month—January” by Admire Mavolwane Zimbabwe Independent (Harare) Feb. 9, 2007. (source: Double-Tongued Dictionary)