By 1978, there were enough of these phenomena to merit a special issue. [fact]
However, research by financial economists in the 1970s and the 1980s pointed to a wider range of phenomena that potentially were inconsistent with the efficient-market hypothesis. By 1978, there were enough of these phenomena to merit a special issue of the new journal of Financial Economics devoted to them.
Donald MacKenzie, An Engine, Not a Camera, loc. 419