How rare this week is

From The Big Picture:

Markets have just lived through 4 consecutive 90% Trading Days. That is a session where 90% of the stock trading volume and the number of advancers versus decliners is to one sided. These 90% Days are defined by their extreme intensity. They are typically associated with panic selling and on occasion, panic buying.

Four consecutive 90% Days is extremely rare, and according to Lowry’s Technical service, this week was “only the second time since 1940 that four consecutive 90% Days have been registered.” Floyd Norris of the NYT found 3 instances of consecutive 4+% swings.