Late July has a reputation in financial markets, and it is earning it again this year. Trading volume thins out, institutional desks empty as portfolio managers take vacation, and major indices tend to drift sideways in a pattern traders have long called the summer doldrums. This year that pattern is showing up clearly: after struggling for six weeks to break through previous highs, major indices have settled into a range-bound stretch defined more by low conviction than by any real change in direction.