Traders often wonder whether markets trade differently on certain days of the week. The following analysis, which looks at large one-day declines in Mini Dow stock-index futures (YM), indicates the market behaves differently after drops that occur on Mondays. How useful that tendency is, however, is a different story.

The research was triggered by the market’s action on Monday, June 15, a day on which the market broke sharply lower. The June Mini Dow futures (YMM09) dropped nearly 2.5 percent below the previous day’s close, and finished the session near that low. (The market also made a nine-day low that day, pushing downward out of a short-term consolidation.)

To find out how the Mini Dow futures have behaved after similar moves in the past, the analysis studied daily continuous futures data from April 2, 2002 through June 12, 2009 — a period that was dominated mostly by a bull market but concluded with the most severe downturn since the Great Depression.